// Copyright 2015 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. // Lowering arithmetic (Add(64|32|16|8) ...) => (ADD(Q|L|L|L) ...) (AddPtr ...) => (ADDQ ...) (Add(32|64)F ...) => (ADDS(S|D) ...) (Sub(64|32|16|8) ...) => (SUB(Q|L|L|L) ...) (SubPtr ...) => (SUBQ ...) (Sub(32|64)F ...) => (SUBS(S|D) ...) (Mul(64|32|16|8) ...) => (MUL(Q|L|L|L) ...) (Mul(32|64)F ...) => (MULS(S|D) ...) (Select0 (Mul64uover x y)) => (Select0 (MULQU x y)) (Select0 (Mul32uover x y)) => (Select0 (MULLU x y)) (Select1 (Mul(64|32)uover x y)) => (SETO (Select1 (MUL(Q|L)U x y))) (Hmul(64|32) ...) => (HMUL(Q|L) ...) (Hmul(64|32)u ...) => (HMUL(Q|L)U ...) (Div(64|32|16) [a] x y) => (Select0 (DIV(Q|L|W) [a] x y)) (Div8 x y) => (Select0 (DIVW (SignExt8to16 x) (SignExt8to16 y))) (Div(64|32|16)u x y) => (Select0 (DIV(Q|L|W)U x y)) (Div8u x y) => (Select0 (DIVWU (ZeroExt8to16 x) (ZeroExt8to16 y))) (Div(32|64)F ...) => (DIVS(S|D) ...) (Select0 (Add64carry x y c)) => (Select0 (ADCQ x y (Select1 (NEGLflags c)))) (Select1 (Add64carry x y c)) => (NEGQ (SBBQcarrymask (Select1 (ADCQ x y (Select1 (NEGLflags c)))))) (Select0 (Sub64borrow x y c)) => (Select0 (SBBQ x y (Select1 (NEGLflags c)))) (Select1 (Sub64borrow x y c)) => (NEGQ (SBBQcarrymask (Select1 (SBBQ x y (Select1 (NEGLflags c)))))) // Optimize ADCQ and friends (ADCQ x (MOVQconst [c]) carry) && is32Bit(c) => (ADCQconst x [int32(c)] carry) (ADCQ x y (FlagEQ)) => (ADDQcarry x y) (ADCQconst x [c] (FlagEQ)) => (ADDQconstcarry x [c]) (ADDQcarry x (MOVQconst [c])) && is32Bit(c) => (ADDQconstcarry x [int32(c)]) (SBBQ x (MOVQconst [c]) borrow) && is32Bit(c) => (SBBQconst x [int32(c)] borrow) (SBBQ x y (FlagEQ)) => (SUBQborrow x y) (SBBQconst x [c] (FlagEQ)) => (SUBQconstborrow x [c]) (SUBQborrow x (MOVQconst [c])) && is32Bit(c) => (SUBQconstborrow x [int32(c)]) (Select1 (NEGLflags (MOVQconst [0]))) => (FlagEQ) (Select1 (NEGLflags (NEGQ (SBBQcarrymask x)))) => x (Mul64uhilo ...) => (MULQU2 ...) (Div128u ...) => (DIVQU2 ...) (Avg64u ...) => (AVGQU ...) (Mod(64|32|16) [a] x y) => (Select1 (DIV(Q|L|W) [a] x y)) (Mod8 x y) => (Select1 (DIVW (SignExt8to16 x) (SignExt8to16 y))) (Mod(64|32|16)u x y) => (Select1 (DIV(Q|L|W)U x y)) (Mod8u x y) => (Select1 (DIVWU (ZeroExt8to16 x) (ZeroExt8to16 y))) (And(64|32|16|8) ...) => (AND(Q|L|L|L) ...) (Or(64|32|16|8) ...) => (OR(Q|L|L|L) ...) (Xor(64|32|16|8) ...) => (XOR(Q|L|L|L) ...) (Com(64|32|16|8) ...) => (NOT(Q|L|L|L) ...) (Neg(64|32|16|8) ...) => (NEG(Q|L|L|L) ...) (Neg32F x) => (PXOR x (MOVSSconst [float32(math.Copysign(0, -1))])) (Neg64F x) => (PXOR x (MOVSDconst [math.Copysign(0, -1)])) // Lowering boolean ops (AndB ...) => (ANDL ...) (OrB ...) => (ORL ...) (Not x) => (XORLconst [1] x) // Lowering pointer arithmetic (OffPtr [off] ptr) && is32Bit(off) => (ADDQconst [int32(off)] ptr) (OffPtr [off] ptr) => (ADDQ (MOVQconst [off]) ptr) // Lowering other arithmetic (Ctz64 x) && buildcfg.GOAMD64 >= 3 => (TZCNTQ x) (Ctz32 x) && buildcfg.GOAMD64 >= 3 => (TZCNTL x) (Ctz64 x) && buildcfg.GOAMD64 < 3 => (CMOVQEQ (Select0 (BSFQ x)) (MOVQconst [64]) (Select1 (BSFQ x))) (Ctz32 x) && buildcfg.GOAMD64 < 3 => (Select0 (BSFQ (BTSQconst [32] x))) (Ctz16 x) => (BSFL (BTSLconst [16] x)) (Ctz8 x) => (BSFL (BTSLconst [ 8] x)) (Ctz64NonZero x) && buildcfg.GOAMD64 >= 3 => (TZCNTQ x) (Ctz32NonZero x) && buildcfg.GOAMD64 >= 3 => (TZCNTL x) (Ctz16NonZero x) && buildcfg.GOAMD64 >= 3 => (TZCNTL x) (Ctz8NonZero x) && buildcfg.GOAMD64 >= 3 => (TZCNTL x) (Ctz64NonZero x) && buildcfg.GOAMD64 < 3 => (Select0 (BSFQ x)) (Ctz32NonZero x) && buildcfg.GOAMD64 < 3 => (BSFL x) (Ctz16NonZero x) && buildcfg.GOAMD64 < 3 => (BSFL x) (Ctz8NonZero x) && buildcfg.GOAMD64 < 3 => (BSFL x) // BitLen64 of a 64 bit value x requires checking whether x == 0, since BSRQ is undefined when x == 0. // However, for zero-extended values, we can cheat a bit, and calculate // BSR(x<<1 + 1), which is guaranteed to be non-zero, and which conveniently // places the index of the highest set bit where we want it. (BitLen64 x) => (ADDQconst [1] (CMOVQEQ (Select0 (BSRQ x)) (MOVQconst [-1]) (Select1 (BSRQ x)))) (BitLen32 x) => (Select0 (BSRQ (LEAQ1 [1] (MOVLQZX x) (MOVLQZX x)))) (BitLen16 x) => (BSRL (LEAL1 [1] (MOVWQZX x) (MOVWQZX x))) (BitLen8 x) => (BSRL (LEAL1 [1] (MOVBQZX x) (MOVBQZX x))) (Bswap(64|32) ...) => (BSWAP(Q|L) ...) (PopCount(64|32) ...) => (POPCNT(Q|L) ...) (PopCount16 x) => (POPCNTL (MOVWQZX x)) (PopCount8 x) => (POPCNTL (MOVBQZX x)) (Sqrt ...) => (SQRTSD ...) (Sqrt32 ...) => (SQRTSS ...) (RoundToEven x) => (ROUNDSD [0] x) (Floor x) => (ROUNDSD [1] x) (Ceil x) => (ROUNDSD [2] x) (Trunc x) => (ROUNDSD [3] x) (FMA x y z) => (VFMADD231SD z x y) // Lowering extension // Note: we always extend to 64 bits even though some ops don't need that many result bits. (SignExt8to16 ...) => (MOVBQSX ...) (SignExt8to32 ...) => (MOVBQSX ...) (SignExt8to64 ...) => (MOVBQSX ...) (SignExt16to32 ...) => (MOVWQSX ...) (SignExt16to64 ...) => (MOVWQSX ...) (SignExt32to64 ...) => (MOVLQSX ...) (ZeroExt8to16 ...) => (MOVBQZX ...) (ZeroExt8to32 ...) => (MOVBQZX ...) (ZeroExt8to64 ...) => (MOVBQZX ...) (ZeroExt16to32 ...) => (MOVWQZX ...) (ZeroExt16to64 ...) => (MOVWQZX ...) (ZeroExt32to64 ...) => (MOVLQZX ...) (Slicemask x) => (SARQconst (NEGQ x) [63]) (SpectreIndex x y) => (CMOVQCC x (MOVQconst [0]) (CMPQ x y)) (SpectreSliceIndex x y) => (CMOVQHI x (MOVQconst [0]) (CMPQ x y)) // Lowering truncation // Because we ignore high parts of registers, truncates are just copies. (Trunc16to8 ...) => (Copy ...) (Trunc32to8 ...) => (Copy ...) (Trunc32to16 ...) => (Copy ...) (Trunc64to8 ...) => (Copy ...) (Trunc64to16 ...) => (Copy ...) (Trunc64to32 ...) => (Copy ...) // Lowering float <-> int (Cvt32to32F ...) => (CVTSL2SS ...) (Cvt32to64F ...) => (CVTSL2SD ...) (Cvt64to32F ...) => (CVTSQ2SS ...) (Cvt64to64F ...) => (CVTSQ2SD ...) (Cvt32Fto32 ...) => (CVTTSS2SL ...) (Cvt32Fto64 ...) => (CVTTSS2SQ ...) (Cvt64Fto32 ...) => (CVTTSD2SL ...) (Cvt64Fto64 ...) => (CVTTSD2SQ ...) (Cvt32Fto64F ...) => (CVTSS2SD ...) (Cvt64Fto32F ...) => (CVTSD2SS ...) (Round(32|64)F ...) => (Copy ...) (CvtBoolToUint8 ...) => (Copy ...) // Lowering shifts // Unsigned shifts need to return 0 if shift amount is >= width of shifted value. // result = (arg << shift) & (shift >= argbits ? 0 : 0xffffffffffffffff) (Lsh64x(64|32|16|8) x y) && !shiftIsBounded(v) => (ANDQ (SHLQ x y) (SBBQcarrymask (CMP(Q|L|W|B)const y [64]))) (Lsh32x(64|32|16|8) x y) && !shiftIsBounded(v) => (ANDL (SHLL x y) (SBBLcarrymask (CMP(Q|L|W|B)const y [32]))) (Lsh16x(64|32|16|8) x y) && !shiftIsBounded(v) => (ANDL (SHLL x y) (SBBLcarrymask (CMP(Q|L|W|B)const y [32]))) (Lsh8x(64|32|16|8) x y) && !shiftIsBounded(v) => (ANDL (SHLL x y) (SBBLcarrymask (CMP(Q|L|W|B)const y [32]))) (Lsh64x(64|32|16|8) x y) && shiftIsBounded(v) => (SHLQ x y) (Lsh32x(64|32|16|8) x y) && shiftIsBounded(v) => (SHLL x y) (Lsh16x(64|32|16|8) x y) && shiftIsBounded(v) => (SHLL x y) (Lsh8x(64|32|16|8) x y) && shiftIsBounded(v) => (SHLL x y) (Rsh64Ux(64|32|16|8) x y) && !shiftIsBounded(v) => (ANDQ (SHRQ x y) (SBBQcarrymask (CMP(Q|L|W|B)const y [64]))) (Rsh32Ux(64|32|16|8) x y) && !shiftIsBounded(v) => (ANDL (SHRL x y) (SBBLcarrymask (CMP(Q|L|W|B)const y [32]))) (Rsh16Ux(64|32|16|8) x y) && !shiftIsBounded(v) => (ANDL (SHRW x y) (SBBLcarrymask (CMP(Q|L|W|B)const y [16]))) (Rsh8Ux(64|32|16|8) x y) && !shiftIsBounded(v) => (ANDL (SHRB x y) (SBBLcarrymask (CMP(Q|L|W|B)const y [8]))) (Rsh64Ux(64|32|16|8) x y) && shiftIsBounded(v) => (SHRQ x y) (Rsh32Ux(64|32|16|8) x y) && shiftIsBounded(v) => (SHRL x y) (Rsh16Ux(64|32|16|8) x y) && shiftIsBounded(v) => (SHRW x y) (Rsh8Ux(64|32|16|8) x y) && shiftIsBounded(v) => (SHRB x y) // Signed right shift needs to return 0/-1 if shift amount is >= width of shifted value. // We implement this by setting the shift value to -1 (all ones) if the shift value is >= width. (Rsh64x(64|32|16|8) x y) && !shiftIsBounded(v) => (SARQ x (OR(Q|L|L|L) y (NOT(Q|L|L|L) (SBB(Q|L|L|L)carrymask (CMP(Q|L|W|B)const y [64]))))) (Rsh32x(64|32|16|8) x y) && !shiftIsBounded(v) => (SARL x (OR(Q|L|L|L) y (NOT(Q|L|L|L) (SBB(Q|L|L|L)carrymask (CMP(Q|L|W|B)const y [32]))))) (Rsh16x(64|32|16|8) x y) && !shiftIsBounded(v) => (SARW x (OR(Q|L|L|L) y (NOT(Q|L|L|L) (SBB(Q|L|L|L)carrymask (CMP(Q|L|W|B)const y [16]))))) (Rsh8x(64|32|16|8) x y) && !shiftIsBounded(v) => (SARB x (OR(Q|L|L|L) y (NOT(Q|L|L|L) (SBB(Q|L|L|L)carrymask (CMP(Q|L|W|B)const y [8]))))) (Rsh64x(64|32|16|8) x y) && shiftIsBounded(v) => (SARQ x y) (Rsh32x(64|32|16|8) x y) && shiftIsBounded(v) => (SARL x y) (Rsh16x(64|32|16|8) x y) && shiftIsBounded(v) => (SARW x y) (Rsh8x(64|32|16|8) x y) && shiftIsBounded(v) => (SARB x y) // Lowering integer comparisons (Less(64|32|16|8) x y) => (SETL (CMP(Q|L|W|B) x y)) (Less(64|32|16|8)U x y) => (SETB (CMP(Q|L|W|B) x y)) (Leq(64|32|16|8) x y) => (SETLE (CMP(Q|L|W|B) x y)) (Leq(64|32|16|8)U x y) => (SETBE (CMP(Q|L|W|B) x y)) (Eq(Ptr|64|32|16|8|B) x y) => (SETEQ (CMP(Q|Q|L|W|B|B) x y)) (Neq(Ptr|64|32|16|8|B) x y) => (SETNE (CMP(Q|Q|L|W|B|B) x y)) // Lowering floating point comparisons // Note Go assembler gets UCOMISx operand order wrong, but it is right here // and the operands are reversed when generating assembly language. (Eq(32|64)F x y) => (SETEQF (UCOMIS(S|D) x y)) (Neq(32|64)F x y) => (SETNEF (UCOMIS(S|D) x y)) // Use SETGF/SETGEF with reversed operands to dodge NaN case. (Less(32|64)F x y) => (SETGF (UCOMIS(S|D) y x)) (Leq(32|64)F x y) => (SETGEF (UCOMIS(S|D) y x)) // Lowering loads (Load ptr mem) && (is64BitInt(t) || isPtr(t)) => (MOVQload ptr mem) (Load ptr mem) && is32BitInt(t) => (MOVLload ptr mem) (Load ptr mem) && is16BitInt(t) => (MOVWload ptr mem) (Load ptr mem) && (t.IsBoolean() || is8BitInt(t)) => (MOVBload ptr mem) (Load ptr mem) && is32BitFloat(t) => (MOVSSload ptr mem) (Load ptr mem) && is64BitFloat(t) => (MOVSDload ptr mem) // Lowering stores // These more-specific FP versions of Store pattern should come first. (Store {t} ptr val mem) && t.Size() == 8 && is64BitFloat(val.Type) => (MOVSDstore ptr val mem) (Store {t} ptr val mem) && t.Size() == 4 && is32BitFloat(val.Type) => (MOVSSstore ptr val mem) (Store {t} ptr val mem) && t.Size() == 8 => (MOVQstore ptr val mem) (Store {t} ptr val mem) && t.Size() == 4 => (MOVLstore ptr val mem) (Store {t} ptr val mem) && t.Size() == 2 => (MOVWstore ptr val mem) (Store {t} ptr val mem) && t.Size() == 1 => (MOVBstore ptr val mem) // Lowering moves (Move [0] _ _ mem) => mem (Move [1] dst src mem) => (MOVBstore dst (MOVBload src mem) mem) (Move [2] dst src mem) => (MOVWstore dst (MOVWload src mem) mem) (Move [4] dst src mem) => (MOVLstore dst (MOVLload src mem) mem) (Move [8] dst src mem) => (MOVQstore dst (MOVQload src mem) mem) (Move [16] dst src mem) && config.useSSE => (MOVOstore dst (MOVOload src mem) mem) (Move [16] dst src mem) && !config.useSSE => (MOVQstore [8] dst (MOVQload [8] src mem) (MOVQstore dst (MOVQload src mem) mem)) (Move [32] dst src mem) => (Move [16] (OffPtr dst [16]) (OffPtr src [16]) (Move [16] dst src mem)) (Move [48] dst src mem) && config.useSSE => (Move [32] (OffPtr dst [16]) (OffPtr src [16]) (Move [16] dst src mem)) (Move [64] dst src mem) && config.useSSE => (Move [32] (OffPtr dst [32]) (OffPtr src [32]) (Move [32] dst src mem)) (Move [3] dst src mem) => (MOVBstore [2] dst (MOVBload [2] src mem) (MOVWstore dst (MOVWload src mem) mem)) (Move [5] dst src mem) => (MOVBstore [4] dst (MOVBload [4] src mem) (MOVLstore dst (MOVLload src mem) mem)) (Move [6] dst src mem) => (MOVWstore [4] dst (MOVWload [4] src mem) (MOVLstore dst (MOVLload src mem) mem)) (Move [7] dst src mem) => (MOVLstore [3] dst (MOVLload [3] src mem) (MOVLstore dst (MOVLload src mem) mem)) (Move [9] dst src mem) => (MOVBstore [8] dst (MOVBload [8] src mem) (MOVQstore dst (MOVQload src mem) mem)) (Move [10] dst src mem) => (MOVWstore [8] dst (MOVWload [8] src mem) (MOVQstore dst (MOVQload src mem) mem)) (Move [12] dst src mem) => (MOVLstore [8] dst (MOVLload [8] src mem) (MOVQstore dst (MOVQload src mem) mem)) (Move [s] dst src mem) && s == 11 || s >= 13 && s <= 15 => (MOVQstore [int32(s-8)] dst (MOVQload [int32(s-8)] src mem) (MOVQstore dst (MOVQload src mem) mem)) // Adjust moves to be a multiple of 16 bytes. (Move [s] dst src mem) && s > 16 && s%16 != 0 && s%16 <= 8 => (Move [s-s%16] (OffPtr dst [s%16]) (OffPtr src [s%16]) (MOVQstore dst (MOVQload src mem) mem)) (Move [s] dst src mem) && s > 16 && s%16 != 0 && s%16 > 8 && config.useSSE => (Move [s-s%16] (OffPtr dst [s%16]) (OffPtr src [s%16]) (MOVOstore dst (MOVOload src mem) mem)) (Move [s] dst src mem) && s > 16 && s%16 != 0 && s%16 > 8 && !config.useSSE => (Move [s-s%16] (OffPtr dst [s%16]) (OffPtr src [s%16]) (MOVQstore [8] dst (MOVQload [8] src mem) (MOVQstore dst (MOVQload src mem) mem))) // Medium copying uses a duff device. (Move [s] dst src mem) && s > 64 && s <= 16*64 && s%16 == 0 && !config.noDuffDevice && logLargeCopy(v, s) => (DUFFCOPY [s] dst src mem) // Large copying uses REP MOVSQ. (Move [s] dst src mem) && (s > 16*64 || config.noDuffDevice) && s%8 == 0 && logLargeCopy(v, s) => (REPMOVSQ dst src (MOVQconst [s/8]) mem) // Lowering Zero instructions (Zero [0] _ mem) => mem (Zero [1] destptr mem) => (MOVBstoreconst [makeValAndOff(0,0)] destptr mem) (Zero [2] destptr mem) => (MOVWstoreconst [makeValAndOff(0,0)] destptr mem) (Zero [4] destptr mem) => (MOVLstoreconst [makeValAndOff(0,0)] destptr mem) (Zero [8] destptr mem) => (MOVQstoreconst [makeValAndOff(0,0)] destptr mem) (Zero [3] destptr mem) => (MOVBstoreconst [makeValAndOff(0,2)] destptr (MOVWstoreconst [makeValAndOff(0,0)] destptr mem)) (Zero [5] destptr mem) => (MOVBstoreconst [makeValAndOff(0,4)] destptr (MOVLstoreconst [makeValAndOff(0,0)] destptr mem)) (Zero [6] destptr mem) => (MOVWstoreconst [makeValAndOff(0,4)] destptr (MOVLstoreconst [makeValAndOff(0,0)] destptr mem)) (Zero [7] destptr mem) => (MOVLstoreconst [makeValAndOff(0,3)] destptr (MOVLstoreconst [makeValAndOff(0,0)] destptr mem)) // Strip off any fractional word zeroing. (Zero [s] destptr mem) && s%8 != 0 && s > 8 && !config.useSSE => (Zero [s-s%8] (OffPtr destptr [s%8]) (MOVQstoreconst [makeValAndOff(0,0)] destptr mem)) // Zero small numbers of words directly. (Zero [16] destptr mem) && !config.useSSE => (MOVQstoreconst [makeValAndOff(0,8)] destptr (MOVQstoreconst [makeValAndOff(0,0)] destptr mem)) (Zero [24] destptr mem) && !config.useSSE => (MOVQstoreconst [makeValAndOff(0,16)] destptr (MOVQstoreconst [makeValAndOff(0,8)] destptr (MOVQstoreconst [makeValAndOff(0,0)] destptr mem))) (Zero [32] destptr mem) && !config.useSSE => (MOVQstoreconst [makeValAndOff(0,24)] destptr (MOVQstoreconst [makeValAndOff(0,16)] destptr (MOVQstoreconst [makeValAndOff(0,8)] destptr (MOVQstoreconst [makeValAndOff(0,0)] destptr mem)))) (Zero [s] destptr mem) && s > 8 && s < 16 && config.useSSE => (MOVQstoreconst [makeValAndOff(0,int32(s-8))] destptr (MOVQstoreconst [makeValAndOff(0,0)] destptr mem)) // Adjust zeros to be a multiple of 16 bytes. (Zero [s] destptr mem) && s%16 != 0 && s > 16 && s%16 > 8 && config.useSSE => (Zero [s-s%16] (OffPtr destptr [s%16]) (MOVOstoreconst [makeValAndOff(0,0)] destptr mem)) (Zero [s] destptr mem) && s%16 != 0 && s > 16 && s%16 <= 8 && config.useSSE => (Zero [s-s%16] (OffPtr destptr [s%16]) (MOVOstoreconst [makeValAndOff(0,0)] destptr mem)) (Zero [16] destptr mem) && config.useSSE => (MOVOstoreconst [makeValAndOff(0,0)] destptr mem) (Zero [32] destptr mem) && config.useSSE => (MOVOstoreconst [makeValAndOff(0,16)] destptr (MOVOstoreconst [makeValAndOff(0,0)] destptr mem)) (Zero [48] destptr mem) && config.useSSE => (MOVOstoreconst [makeValAndOff(0,32)] destptr (MOVOstoreconst [makeValAndOff(0,16)] destptr (MOVOstoreconst [makeValAndOff(0,0)] destptr mem))) (Zero [64] destptr mem) && config.useSSE => (MOVOstoreconst [makeValAndOff(0,48)] destptr (MOVOstoreconst [makeValAndOff(0,32)] destptr (MOVOstoreconst [makeValAndOff(0,16)] destptr (MOVOstoreconst [makeValAndOff(0,0)] destptr mem)))) // Medium zeroing uses a duff device. (Zero [s] destptr mem) && s > 64 && s <= 1024 && s%16 == 0 && !config.noDuffDevice => (DUFFZERO [s] destptr mem) // Large zeroing uses REP STOSQ. (Zero [s] destptr mem) && (s > 1024 || (config.noDuffDevice && s > 64 || !config.useSSE && s > 32)) && s%8 == 0 => (REPSTOSQ destptr (MOVQconst [s/8]) (MOVQconst [0]) mem) // Lowering constants (Const8 [c]) => (MOVLconst [int32(c)]) (Const16 [c]) => (MOVLconst [int32(c)]) (Const32 ...) => (MOVLconst ...) (Const64 ...) => (MOVQconst ...) (Const32F ...) => (MOVSSconst ...) (Const64F ...) => (MOVSDconst ...) (ConstNil ) => (MOVQconst [0]) (ConstBool [c]) => (MOVLconst [b2i32(c)]) // Lowering calls (StaticCall ...) => (CALLstatic ...) (ClosureCall ...) => (CALLclosure ...) (InterCall ...) => (CALLinter ...) (TailCall ...) => (CALLtail ...) // Lowering conditional moves // If the condition is a SETxx, we can just run a CMOV from the comparison that was // setting the flags. // Legend: HI=unsigned ABOVE, CS=unsigned BELOW, CC=unsigned ABOVE EQUAL, LS=unsigned BELOW EQUAL (CondSelect x y (SET(EQ|NE|L|G|LE|GE|A|B|AE|BE|EQF|NEF|GF|GEF) cond)) && (is64BitInt(t) || isPtr(t)) => (CMOVQ(EQ|NE|LT|GT|LE|GE|HI|CS|CC|LS|EQF|NEF|GTF|GEF) y x cond) (CondSelect x y (SET(EQ|NE|L|G|LE|GE|A|B|AE|BE|EQF|NEF|GF|GEF) cond)) && is32BitInt(t) => (CMOVL(EQ|NE|LT|GT|LE|GE|HI|CS|CC|LS|EQF|NEF|GTF|GEF) y x cond) (CondSelect x y (SET(EQ|NE|L|G|LE|GE|A|B|AE|BE|EQF|NEF|GF|GEF) cond)) && is16BitInt(t) => (CMOVW(EQ|NE|LT|GT|LE|GE|HI|CS|CC|LS|EQF|NEF|GTF|GEF) y x cond) // If the condition does not set the flags, we need to generate a comparison. (CondSelect x y check) && !check.Type.IsFlags() && check.Type.Size() == 1 => (CondSelect x y (MOVBQZX check)) (CondSelect x y check) && !check.Type.IsFlags() && check.Type.Size() == 2 => (CondSelect x y (MOVWQZX check)) (CondSelect x y check) && !check.Type.IsFlags() && check.Type.Size() == 4 => (CondSelect x y (MOVLQZX check)) (CondSelect x y check) && !check.Type.IsFlags() && check.Type.Size() == 8 && (is64BitInt(t) || isPtr(t)) => (CMOVQNE y x (CMPQconst [0] check)) (CondSelect x y check) && !check.Type.IsFlags() && check.Type.Size() == 8 && is32BitInt(t) => (CMOVLNE y x (CMPQconst [0] check)) (CondSelect x y check) && !check.Type.IsFlags() && check.Type.Size() == 8 && is16BitInt(t) => (CMOVWNE y x (CMPQconst [0] check)) // Absorb InvertFlags (CMOVQ(EQ|NE|LT|GT|LE|GE|HI|CS|CC|LS) x y (InvertFlags cond)) => (CMOVQ(EQ|NE|GT|LT|GE|LE|CS|HI|LS|CC) x y cond) (CMOVL(EQ|NE|LT|GT|LE|GE|HI|CS|CC|LS) x y (InvertFlags cond)) => (CMOVL(EQ|NE|GT|LT|GE|LE|CS|HI|LS|CC) x y cond) (CMOVW(EQ|NE|LT|GT|LE|GE|HI|CS|CC|LS) x y (InvertFlags cond)) => (CMOVW(EQ|NE|GT|LT|GE|LE|CS|HI|LS|CC) x y cond) // Absorb constants generated during lower (CMOV(QEQ|QLE|QGE|QCC|QLS|LEQ|LLE|LGE|LCC|LLS|WEQ|WLE|WGE|WCC|WLS) _ x (FlagEQ)) => x (CMOV(QNE|QLT|QGT|QCS|QHI|LNE|LLT|LGT|LCS|LHI|WNE|WLT|WGT|WCS|WHI) y _ (FlagEQ)) => y (CMOV(QNE|QGT|QGE|QHI|QCC|LNE|LGT|LGE|LHI|LCC|WNE|WGT|WGE|WHI|WCC) _ x (FlagGT_UGT)) => x (CMOV(QEQ|QLE|QLT|QLS|QCS|LEQ|LLE|LLT|LLS|LCS|WEQ|WLE|WLT|WLS|WCS) y _ (FlagGT_UGT)) => y (CMOV(QNE|QGT|QGE|QLS|QCS|LNE|LGT|LGE|LLS|LCS|WNE|WGT|WGE|WLS|WCS) _ x (FlagGT_ULT)) => x (CMOV(QEQ|QLE|QLT|QHI|QCC|LEQ|LLE|LLT|LHI|LCC|WEQ|WLE|WLT|WHI|WCC) y _ (FlagGT_ULT)) => y (CMOV(QNE|QLT|QLE|QCS|QLS|LNE|LLT|LLE|LCS|LLS|WNE|WLT|WLE|WCS|WLS) _ x (FlagLT_ULT)) => x (CMOV(QEQ|QGT|QGE|QHI|QCC|LEQ|LGT|LGE|LHI|LCC|WEQ|WGT|WGE|WHI|WCC) y _ (FlagLT_ULT)) => y (CMOV(QNE|QLT|QLE|QHI|QCC|LNE|LLT|LLE|LHI|LCC|WNE|WLT|WLE|WHI|WCC) _ x (FlagLT_UGT)) => x (CMOV(QEQ|QGT|QGE|QCS|QLS|LEQ|LGT|LGE|LCS|LLS|WEQ|WGT|WGE|WCS|WLS) y _ (FlagLT_UGT)) => y // Miscellaneous (IsNonNil p) => (SETNE (TESTQ p p)) (IsInBounds idx len) => (SETB (CMPQ idx len)) (IsSliceInBounds idx len) => (SETBE (CMPQ idx len)) (NilCheck ...) => (LoweredNilCheck ...) (GetG mem) && v.Block.Func.OwnAux.Fn.ABI() != obj.ABIInternal => (LoweredGetG mem) // only lower in old ABI. in new ABI we have a G register. (GetClosurePtr ...) => (LoweredGetClosurePtr ...) (GetCallerPC ...) => (LoweredGetCallerPC ...) (GetCallerSP ...) => (LoweredGetCallerSP ...) (HasCPUFeature {s}) => (SETNE (CMPLconst [0] (LoweredHasCPUFeature {s}))) (Addr {sym} base) => (LEAQ {sym} base) (LocalAddr {sym} base _) => (LEAQ {sym} base) (MOVBstore [off] {sym} ptr y:(SETL x) mem) && y.Uses == 1 => (SETLstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr y:(SETLE x) mem) && y.Uses == 1 => (SETLEstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr y:(SETG x) mem) && y.Uses == 1 => (SETGstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr y:(SETGE x) mem) && y.Uses == 1 => (SETGEstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr y:(SETEQ x) mem) && y.Uses == 1 => (SETEQstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr y:(SETNE x) mem) && y.Uses == 1 => (SETNEstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr y:(SETB x) mem) && y.Uses == 1 => (SETBstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr y:(SETBE x) mem) && y.Uses == 1 => (SETBEstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr y:(SETA x) mem) && y.Uses == 1 => (SETAstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr y:(SETAE x) mem) && y.Uses == 1 => (SETAEstore [off] {sym} ptr x mem) // block rewrites (If (SETL cmp) yes no) => (LT cmp yes no) (If (SETLE cmp) yes no) => (LE cmp yes no) (If (SETG cmp) yes no) => (GT cmp yes no) (If (SETGE cmp) yes no) => (GE cmp yes no) (If (SETEQ cmp) yes no) => (EQ cmp yes no) (If (SETNE cmp) yes no) => (NE cmp yes no) (If (SETB cmp) yes no) => (ULT cmp yes no) (If (SETBE cmp) yes no) => (ULE cmp yes no) (If (SETA cmp) yes no) => (UGT cmp yes no) (If (SETAE cmp) yes no) => (UGE cmp yes no) (If (SETO cmp) yes no) => (OS cmp yes no) // Special case for floating point - LF/LEF not generated (If (SETGF cmp) yes no) => (UGT cmp yes no) (If (SETGEF cmp) yes no) => (UGE cmp yes no) (If (SETEQF cmp) yes no) => (EQF cmp yes no) (If (SETNEF cmp) yes no) => (NEF cmp yes no) (If cond yes no) => (NE (TESTB cond cond) yes no) // Atomic loads. Other than preserving their ordering with respect to other loads, nothing special here. (AtomicLoad8 ptr mem) => (MOVBatomicload ptr mem) (AtomicLoad32 ptr mem) => (MOVLatomicload ptr mem) (AtomicLoad64 ptr mem) => (MOVQatomicload ptr mem) (AtomicLoadPtr ptr mem) => (MOVQatomicload ptr mem) // Atomic stores. We use XCHG to prevent the hardware reordering a subsequent load. // TODO: most runtime uses of atomic stores don't need that property. Use normal stores for those? (AtomicStore8 ptr val mem) => (Select1 (XCHGB val ptr mem)) (AtomicStore32 ptr val mem) => (Select1 (XCHGL val ptr mem)) (AtomicStore64 ptr val mem) => (Select1 (XCHGQ val ptr mem)) (AtomicStorePtrNoWB ptr val mem) => (Select1 (XCHGQ val ptr mem)) // Atomic exchanges. (AtomicExchange32 ptr val mem) => (XCHGL val ptr mem) (AtomicExchange64 ptr val mem) => (XCHGQ val ptr mem) // Atomic adds. (AtomicAdd32 ptr val mem) => (AddTupleFirst32 val (XADDLlock val ptr mem)) (AtomicAdd64 ptr val mem) => (AddTupleFirst64 val (XADDQlock val ptr mem)) (Select0 (AddTupleFirst32 val tuple)) => (ADDL val (Select0 tuple)) (Select1 (AddTupleFirst32 _ tuple)) => (Select1 tuple) (Select0 (AddTupleFirst64 val tuple)) => (ADDQ val (Select0 tuple)) (Select1 (AddTupleFirst64 _ tuple)) => (Select1 tuple) // Atomic compare and swap. (AtomicCompareAndSwap32 ptr old new_ mem) => (CMPXCHGLlock ptr old new_ mem) (AtomicCompareAndSwap64 ptr old new_ mem) => (CMPXCHGQlock ptr old new_ mem) // Atomic memory updates. (AtomicAnd8 ptr val mem) => (ANDBlock ptr val mem) (AtomicAnd32 ptr val mem) => (ANDLlock ptr val mem) (AtomicOr8 ptr val mem) => (ORBlock ptr val mem) (AtomicOr32 ptr val mem) => (ORLlock ptr val mem) // Write barrier. (WB ...) => (LoweredWB ...) (PanicBounds [kind] x y mem) && boundsABI(kind) == 0 => (LoweredPanicBoundsA [kind] x y mem) (PanicBounds [kind] x y mem) && boundsABI(kind) == 1 => (LoweredPanicBoundsB [kind] x y mem) (PanicBounds [kind] x y mem) && boundsABI(kind) == 2 => (LoweredPanicBoundsC [kind] x y mem) // *************************** // Above: lowering rules // Below: optimizations // *************************** // TODO: Should the optimizations be a separate pass? // Fold boolean tests into blocks (NE (TESTB (SETL cmp) (SETL cmp)) yes no) => (LT cmp yes no) (NE (TESTB (SETLE cmp) (SETLE cmp)) yes no) => (LE cmp yes no) (NE (TESTB (SETG cmp) (SETG cmp)) yes no) => (GT cmp yes no) (NE (TESTB (SETGE cmp) (SETGE cmp)) yes no) => (GE cmp yes no) (NE (TESTB (SETEQ cmp) (SETEQ cmp)) yes no) => (EQ cmp yes no) (NE (TESTB (SETNE cmp) (SETNE cmp)) yes no) => (NE cmp yes no) (NE (TESTB (SETB cmp) (SETB cmp)) yes no) => (ULT cmp yes no) (NE (TESTB (SETBE cmp) (SETBE cmp)) yes no) => (ULE cmp yes no) (NE (TESTB (SETA cmp) (SETA cmp)) yes no) => (UGT cmp yes no) (NE (TESTB (SETAE cmp) (SETAE cmp)) yes no) => (UGE cmp yes no) (NE (TESTB (SETO cmp) (SETO cmp)) yes no) => (OS cmp yes no) // Unsigned comparisons to 0/1 (ULT (TEST(Q|L|W|B) x x) yes no) => (First no yes) (UGE (TEST(Q|L|W|B) x x) yes no) => (First yes no) (SETB (TEST(Q|L|W|B) x x)) => (ConstBool [false]) (SETAE (TEST(Q|L|W|B) x x)) => (ConstBool [true]) // x & 1 != 0 -> x & 1 (SETNE (TEST(B|W)const [1] x)) => (AND(L|L)const [1] x) (SETB (BT(L|Q)const [0] x)) => (AND(L|Q)const [1] x) // Recognize bit tests: a&(1< ((ULT|UGE) (BTL x y)) ((NE|EQ) (TESTQ (SHLQ (MOVQconst [1]) x) y)) => ((ULT|UGE) (BTQ x y)) ((NE|EQ) (TESTLconst [c] x)) && isUint32PowerOfTwo(int64(c)) => ((ULT|UGE) (BTLconst [int8(log32(c))] x)) ((NE|EQ) (TESTQconst [c] x)) && isUint64PowerOfTwo(int64(c)) => ((ULT|UGE) (BTQconst [int8(log32(c))] x)) ((NE|EQ) (TESTQ (MOVQconst [c]) x)) && isUint64PowerOfTwo(c) => ((ULT|UGE) (BTQconst [int8(log64(c))] x)) (SET(NE|EQ) (TESTL (SHLL (MOVLconst [1]) x) y)) => (SET(B|AE) (BTL x y)) (SET(NE|EQ) (TESTQ (SHLQ (MOVQconst [1]) x) y)) => (SET(B|AE) (BTQ x y)) (SET(NE|EQ) (TESTLconst [c] x)) && isUint32PowerOfTwo(int64(c)) => (SET(B|AE) (BTLconst [int8(log32(c))] x)) (SET(NE|EQ) (TESTQconst [c] x)) && isUint64PowerOfTwo(int64(c)) => (SET(B|AE) (BTQconst [int8(log32(c))] x)) (SET(NE|EQ) (TESTQ (MOVQconst [c]) x)) && isUint64PowerOfTwo(c) => (SET(B|AE) (BTQconst [int8(log64(c))] x)) // SET..store variant (SET(NE|EQ)store [off] {sym} ptr (TESTL (SHLL (MOVLconst [1]) x) y) mem) => (SET(B|AE)store [off] {sym} ptr (BTL x y) mem) (SET(NE|EQ)store [off] {sym} ptr (TESTQ (SHLQ (MOVQconst [1]) x) y) mem) => (SET(B|AE)store [off] {sym} ptr (BTQ x y) mem) (SET(NE|EQ)store [off] {sym} ptr (TESTLconst [c] x) mem) && isUint32PowerOfTwo(int64(c)) => (SET(B|AE)store [off] {sym} ptr (BTLconst [int8(log32(c))] x) mem) (SET(NE|EQ)store [off] {sym} ptr (TESTQconst [c] x) mem) && isUint64PowerOfTwo(int64(c)) => (SET(B|AE)store [off] {sym} ptr (BTQconst [int8(log32(c))] x) mem) (SET(NE|EQ)store [off] {sym} ptr (TESTQ (MOVQconst [c]) x) mem) && isUint64PowerOfTwo(c) => (SET(B|AE)store [off] {sym} ptr (BTQconst [int8(log64(c))] x) mem) // Handle bit-testing in the form (a>>b)&1 != 0 by building the above rules // and further combining shifts. (BT(Q|L)const [c] (SHRQconst [d] x)) && (c+d)<64 => (BTQconst [c+d] x) (BT(Q|L)const [c] (SHLQconst [d] x)) && c>d => (BT(Q|L)const [c-d] x) (BT(Q|L)const [0] s:(SHRQ x y)) => (BTQ y x) (BTLconst [c] (SHRLconst [d] x)) && (c+d)<32 => (BTLconst [c+d] x) (BTLconst [c] (SHLLconst [d] x)) && c>d => (BTLconst [c-d] x) (BTLconst [0] s:(SHRL x y)) => (BTL y x) // Rewrite a & 1 != 1 into a & 1 == 0. // Among other things, this lets us turn (a>>b)&1 != 1 into a bit test. (SET(NE|EQ) (CMPLconst [1] s:(ANDLconst [1] _))) => (SET(EQ|NE) (CMPLconst [0] s)) (SET(NE|EQ)store [off] {sym} ptr (CMPLconst [1] s:(ANDLconst [1] _)) mem) => (SET(EQ|NE)store [off] {sym} ptr (CMPLconst [0] s) mem) (SET(NE|EQ) (CMPQconst [1] s:(ANDQconst [1] _))) => (SET(EQ|NE) (CMPQconst [0] s)) (SET(NE|EQ)store [off] {sym} ptr (CMPQconst [1] s:(ANDQconst [1] _)) mem) => (SET(EQ|NE)store [off] {sym} ptr (CMPQconst [0] s) mem) // Recognize bit setting (a |= 1< (BTS(Q|L) x y) (XOR(Q|L) (SHL(Q|L) (MOV(Q|L)const [1]) y) x) => (BTC(Q|L) x y) // Convert ORconst into BTS, if the code gets smaller, with boundary being // (ORL $40,AX is 3 bytes, ORL $80,AX is 6 bytes). ((ORQ|XORQ)const [c] x) && isUint64PowerOfTwo(int64(c)) && uint64(c) >= 128 => (BT(S|C)Qconst [int8(log32(c))] x) ((ORL|XORL)const [c] x) && isUint32PowerOfTwo(int64(c)) && uint64(c) >= 128 => (BT(S|C)Lconst [int8(log32(c))] x) ((ORQ|XORQ) (MOVQconst [c]) x) && isUint64PowerOfTwo(c) && uint64(c) >= 128 => (BT(S|C)Qconst [int8(log64(c))] x) ((ORL|XORL) (MOVLconst [c]) x) && isUint32PowerOfTwo(int64(c)) && uint64(c) >= 128 => (BT(S|C)Lconst [int8(log32(c))] x) // Recognize bit clearing: a &^= 1< (BTR(Q|L) x y) (ANDN(Q|L) x (SHL(Q|L) (MOV(Q|L)const [1]) y)) => (BTR(Q|L) x y) (ANDQconst [c] x) && isUint64PowerOfTwo(int64(^c)) && uint64(^c) >= 128 => (BTRQconst [int8(log32(^c))] x) (ANDLconst [c] x) && isUint32PowerOfTwo(int64(^c)) && uint64(^c) >= 128 => (BTRLconst [int8(log32(^c))] x) (ANDQ (MOVQconst [c]) x) && isUint64PowerOfTwo(^c) && uint64(^c) >= 128 => (BTRQconst [int8(log64(^c))] x) (ANDL (MOVLconst [c]) x) && isUint32PowerOfTwo(int64(^c)) && uint64(^c) >= 128 => (BTRLconst [int8(log32(^c))] x) // Special-case bit patterns on first/last bit. // generic.rules changes ANDs of high-part/low-part masks into a couple of shifts, // for instance: // x & 0xFFFF0000 -> (x >> 16) << 16 // x & 0x80000000 -> (x >> 31) << 31 // // In case the mask is just one bit (like second example above), it conflicts // with the above rules to detect bit-testing / bit-clearing of first/last bit. // We thus special-case them, by detecting the shift patterns. // Special case resetting first/last bit (SHL(L|Q)const [1] (SHR(L|Q)const [1] x)) => (BTR(L|Q)const [0] x) (SHRLconst [1] (SHLLconst [1] x)) => (BTRLconst [31] x) (SHRQconst [1] (SHLQconst [1] x)) => (BTRQconst [63] x) // Special case testing first/last bit (with double-shift generated by generic.rules) ((SETNE|SETEQ|NE|EQ) (TESTQ z1:(SHLQconst [63] (SHRQconst [63] x)) z2)) && z1==z2 => ((SETB|SETAE|ULT|UGE) (BTQconst [63] x)) ((SETNE|SETEQ|NE|EQ) (TESTL z1:(SHLLconst [31] (SHRQconst [31] x)) z2)) && z1==z2 => ((SETB|SETAE|ULT|UGE) (BTQconst [31] x)) (SET(NE|EQ)store [off] {sym} ptr (TESTQ z1:(SHLQconst [63] (SHRQconst [63] x)) z2) mem) && z1==z2 => (SET(B|AE)store [off] {sym} ptr (BTQconst [63] x) mem) (SET(NE|EQ)store [off] {sym} ptr (TESTL z1:(SHLLconst [31] (SHRLconst [31] x)) z2) mem) && z1==z2 => (SET(B|AE)store [off] {sym} ptr (BTLconst [31] x) mem) ((SETNE|SETEQ|NE|EQ) (TESTQ z1:(SHRQconst [63] (SHLQconst [63] x)) z2)) && z1==z2 => ((SETB|SETAE|ULT|UGE) (BTQconst [0] x)) ((SETNE|SETEQ|NE|EQ) (TESTL z1:(SHRLconst [31] (SHLLconst [31] x)) z2)) && z1==z2 => ((SETB|SETAE|ULT|UGE) (BTLconst [0] x)) (SET(NE|EQ)store [off] {sym} ptr (TESTQ z1:(SHRQconst [63] (SHLQconst [63] x)) z2) mem) && z1==z2 => (SET(B|AE)store [off] {sym} ptr (BTQconst [0] x) mem) (SET(NE|EQ)store [off] {sym} ptr (TESTL z1:(SHRLconst [31] (SHLLconst [31] x)) z2) mem) && z1==z2 => (SET(B|AE)store [off] {sym} ptr (BTLconst [0] x) mem) // Special-case manually testing last bit with "a>>63 != 0" (without "&1") ((SETNE|SETEQ|NE|EQ) (TESTQ z1:(SHRQconst [63] x) z2)) && z1==z2 => ((SETB|SETAE|ULT|UGE) (BTQconst [63] x)) ((SETNE|SETEQ|NE|EQ) (TESTL z1:(SHRLconst [31] x) z2)) && z1==z2 => ((SETB|SETAE|ULT|UGE) (BTLconst [31] x)) (SET(NE|EQ)store [off] {sym} ptr (TESTQ z1:(SHRQconst [63] x) z2) mem) && z1==z2 => (SET(B|AE)store [off] {sym} ptr (BTQconst [63] x) mem) (SET(NE|EQ)store [off] {sym} ptr (TESTL z1:(SHRLconst [31] x) z2) mem) && z1==z2 => (SET(B|AE)store [off] {sym} ptr (BTLconst [31] x) mem) // Fold combinations of bit ops on same bit. An example is math.Copysign(c,-1) (BTS(Q|L)const [c] (BTR(Q|L)const [c] x)) => (BTS(Q|L)const [c] x) (BTS(Q|L)const [c] (BTC(Q|L)const [c] x)) => (BTS(Q|L)const [c] x) (BTR(Q|L)const [c] (BTS(Q|L)const [c] x)) => (BTR(Q|L)const [c] x) (BTR(Q|L)const [c] (BTC(Q|L)const [c] x)) => (BTR(Q|L)const [c] x) // Fold boolean negation into SETcc. (XORLconst [1] (SETNE x)) => (SETEQ x) (XORLconst [1] (SETEQ x)) => (SETNE x) (XORLconst [1] (SETL x)) => (SETGE x) (XORLconst [1] (SETGE x)) => (SETL x) (XORLconst [1] (SETLE x)) => (SETG x) (XORLconst [1] (SETG x)) => (SETLE x) (XORLconst [1] (SETB x)) => (SETAE x) (XORLconst [1] (SETAE x)) => (SETB x) (XORLconst [1] (SETBE x)) => (SETA x) (XORLconst [1] (SETA x)) => (SETBE x) // Special case for floating point - LF/LEF not generated (NE (TESTB (SETGF cmp) (SETGF cmp)) yes no) => (UGT cmp yes no) (NE (TESTB (SETGEF cmp) (SETGEF cmp)) yes no) => (UGE cmp yes no) (NE (TESTB (SETEQF cmp) (SETEQF cmp)) yes no) => (EQF cmp yes no) (NE (TESTB (SETNEF cmp) (SETNEF cmp)) yes no) => (NEF cmp yes no) // Disabled because it interferes with the pattern match above and makes worse code. // (SETNEF x) => (ORQ (SETNE x) (SETNAN x)) // (SETEQF x) => (ANDQ (SETEQ x) (SETORD x)) // fold constants into instructions (ADDQ x (MOVQconst [c])) && is32Bit(c) => (ADDQconst [int32(c)] x) (ADDQ x (MOVLconst [c])) => (ADDQconst [c] x) (ADDL x (MOVLconst [c])) => (ADDLconst [c] x) (SUBQ x (MOVQconst [c])) && is32Bit(c) => (SUBQconst x [int32(c)]) (SUBQ (MOVQconst [c]) x) && is32Bit(c) => (NEGQ (SUBQconst x [int32(c)])) (SUBL x (MOVLconst [c])) => (SUBLconst x [c]) (SUBL (MOVLconst [c]) x) => (NEGL (SUBLconst x [c])) (MULQ x (MOVQconst [c])) && is32Bit(c) => (MULQconst [int32(c)] x) (MULL x (MOVLconst [c])) => (MULLconst [c] x) (ANDQ x (MOVQconst [c])) && is32Bit(c) => (ANDQconst [int32(c)] x) (ANDL x (MOVLconst [c])) => (ANDLconst [c] x) (AND(L|Q)const [c] (AND(L|Q)const [d] x)) => (AND(L|Q)const [c & d] x) (XOR(L|Q)const [c] (XOR(L|Q)const [d] x)) => (XOR(L|Q)const [c ^ d] x) (OR(L|Q)const [c] (OR(L|Q)const [d] x)) => (OR(L|Q)const [c | d] x) (BTRLconst [c] (ANDLconst [d] x)) => (ANDLconst [d &^ (1< (ANDLconst [c &^ (1< (ANDLconst [^(1< (XORLconst [d ^ 1< (XORLconst [c ^ 1< (XORLconst [1< (ORLconst [d | 1< (ORLconst [c | 1< (ORLconst [1< (ANDQconst [d &^ (1< (ANDQconst [c &^ (1< (ANDQconst [^(1< (XORQconst [d ^ 1< (XORQconst [c ^ 1< (XORQconst [1< (ORQconst [d | 1< (ORQconst [c | 1< (ORQconst [1< (MULLconst [c * d] x) (MULQconst [c] (MULQconst [d] x)) && is32Bit(int64(c)*int64(d)) => (MULQconst [c * d] x) (ORQ x (MOVQconst [c])) && is32Bit(c) => (ORQconst [int32(c)] x) (ORQ x (MOVLconst [c])) => (ORQconst [c] x) (ORL x (MOVLconst [c])) => (ORLconst [c] x) (XORQ x (MOVQconst [c])) && is32Bit(c) => (XORQconst [int32(c)] x) (XORL x (MOVLconst [c])) => (XORLconst [c] x) (SHLQ x (MOV(Q|L)const [c])) => (SHLQconst [int8(c&63)] x) (SHLL x (MOV(Q|L)const [c])) => (SHLLconst [int8(c&31)] x) (SHRQ x (MOV(Q|L)const [c])) => (SHRQconst [int8(c&63)] x) (SHRL x (MOV(Q|L)const [c])) => (SHRLconst [int8(c&31)] x) (SHRW x (MOV(Q|L)const [c])) && c&31 < 16 => (SHRWconst [int8(c&31)] x) (SHRW _ (MOV(Q|L)const [c])) && c&31 >= 16 => (MOVLconst [0]) (SHRB x (MOV(Q|L)const [c])) && c&31 < 8 => (SHRBconst [int8(c&31)] x) (SHRB _ (MOV(Q|L)const [c])) && c&31 >= 8 => (MOVLconst [0]) (SARQ x (MOV(Q|L)const [c])) => (SARQconst [int8(c&63)] x) (SARL x (MOV(Q|L)const [c])) => (SARLconst [int8(c&31)] x) (SARW x (MOV(Q|L)const [c])) => (SARWconst [int8(min(int64(c)&31,15))] x) (SARB x (MOV(Q|L)const [c])) => (SARBconst [int8(min(int64(c)&31,7))] x) // Operations which don't affect the low 6/5 bits of the shift amount are NOPs. ((SHLQ|SHRQ|SARQ) x (ADDQconst [c] y)) && c & 63 == 0 => ((SHLQ|SHRQ|SARQ) x y) ((SHLQ|SHRQ|SARQ) x (NEGQ (ADDQconst [c] y))) && c & 63 == 0 => ((SHLQ|SHRQ|SARQ) x (NEGQ y)) ((SHLQ|SHRQ|SARQ) x (ANDQconst [c] y)) && c & 63 == 63 => ((SHLQ|SHRQ|SARQ) x y) ((SHLQ|SHRQ|SARQ) x (NEGQ (ANDQconst [c] y))) && c & 63 == 63 => ((SHLQ|SHRQ|SARQ) x (NEGQ y)) ((SHLL|SHRL|SARL) x (ADDQconst [c] y)) && c & 31 == 0 => ((SHLL|SHRL|SARL) x y) ((SHLL|SHRL|SARL) x (NEGQ (ADDQconst [c] y))) && c & 31 == 0 => ((SHLL|SHRL|SARL) x (NEGQ y)) ((SHLL|SHRL|SARL) x (ANDQconst [c] y)) && c & 31 == 31 => ((SHLL|SHRL|SARL) x y) ((SHLL|SHRL|SARL) x (NEGQ (ANDQconst [c] y))) && c & 31 == 31 => ((SHLL|SHRL|SARL) x (NEGQ y)) ((SHLQ|SHRQ|SARQ) x (ADDLconst [c] y)) && c & 63 == 0 => ((SHLQ|SHRQ|SARQ) x y) ((SHLQ|SHRQ|SARQ) x (NEGL (ADDLconst [c] y))) && c & 63 == 0 => ((SHLQ|SHRQ|SARQ) x (NEGL y)) ((SHLQ|SHRQ|SARQ) x (ANDLconst [c] y)) && c & 63 == 63 => ((SHLQ|SHRQ|SARQ) x y) ((SHLQ|SHRQ|SARQ) x (NEGL (ANDLconst [c] y))) && c & 63 == 63 => ((SHLQ|SHRQ|SARQ) x (NEGL y)) ((SHLL|SHRL|SARL) x (ADDLconst [c] y)) && c & 31 == 0 => ((SHLL|SHRL|SARL) x y) ((SHLL|SHRL|SARL) x (NEGL (ADDLconst [c] y))) && c & 31 == 0 => ((SHLL|SHRL|SARL) x (NEGL y)) ((SHLL|SHRL|SARL) x (ANDLconst [c] y)) && c & 31 == 31 => ((SHLL|SHRL|SARL) x y) ((SHLL|SHRL|SARL) x (NEGL (ANDLconst [c] y))) && c & 31 == 31 => ((SHLL|SHRL|SARL) x (NEGL y)) // Constant rotate instructions ((ADDQ|ORQ|XORQ) (SHLQconst x [c]) (SHRQconst x [d])) && d==64-c => (ROLQconst x [c]) ((ADDL|ORL|XORL) (SHLLconst x [c]) (SHRLconst x [d])) && d==32-c => (ROLLconst x [c]) ((ADDL|ORL|XORL) (SHLLconst x [c]) (SHRWconst x [d])) && d==16-c && c < 16 && t.Size() == 2 => (ROLWconst x [c]) ((ADDL|ORL|XORL) (SHLLconst x [c]) (SHRBconst x [d])) && d==8-c && c < 8 && t.Size() == 1 => (ROLBconst x [c]) (ROLQconst [c] (ROLQconst [d] x)) => (ROLQconst [(c+d)&63] x) (ROLLconst [c] (ROLLconst [d] x)) => (ROLLconst [(c+d)&31] x) (ROLWconst [c] (ROLWconst [d] x)) => (ROLWconst [(c+d)&15] x) (ROLBconst [c] (ROLBconst [d] x)) => (ROLBconst [(c+d)& 7] x) (RotateLeft8 ...) => (ROLB ...) (RotateLeft16 ...) => (ROLW ...) (RotateLeft32 ...) => (ROLL ...) (RotateLeft64 ...) => (ROLQ ...) // Non-constant rotates. // We want to issue a rotate when the Go source contains code like // y &= 63 // x << y | x >> (64-y) // The shift rules above convert << to SHLx and >> to SHRx. // SHRx converts its shift argument from 64-y to -y. // A tricky situation occurs when y==0. Then the original code would be: // x << 0 | x >> 64 // But x >> 64 is 0, not x. So there's an additional mask that is ANDed in // to force the second term to 0. We don't need that mask, but we must match // it in order to strip it out. (ORQ (SHLQ x y) (ANDQ (SHRQ x (NEG(Q|L) y)) (SBBQcarrymask (CMP(Q|L)const (NEG(Q|L) (ADD(Q|L)const (AND(Q|L)const y [63]) [-64])) [64])))) => (ROLQ x y) (ORQ (SHRQ x y) (ANDQ (SHLQ x (NEG(Q|L) y)) (SBBQcarrymask (CMP(Q|L)const (NEG(Q|L) (ADD(Q|L)const (AND(Q|L)const y [63]) [-64])) [64])))) => (RORQ x y) (ORL (SHLL x y) (ANDL (SHRL x (NEG(Q|L) y)) (SBBLcarrymask (CMP(Q|L)const (NEG(Q|L) (ADD(Q|L)const (AND(Q|L)const y [31]) [-32])) [32])))) => (ROLL x y) (ORL (SHRL x y) (ANDL (SHLL x (NEG(Q|L) y)) (SBBLcarrymask (CMP(Q|L)const (NEG(Q|L) (ADD(Q|L)const (AND(Q|L)const y [31]) [-32])) [32])))) => (RORL x y) // Help with rotate detection (CMPQconst (NEGQ (ADDQconst [-16] (ANDQconst [15] _))) [32]) => (FlagLT_ULT) (CMPQconst (NEGQ (ADDQconst [ -8] (ANDQconst [7] _))) [32]) => (FlagLT_ULT) (ORL (SHLL x (AND(Q|L)const y [15])) (ANDL (SHRW x (NEG(Q|L) (ADD(Q|L)const (AND(Q|L)const y [15]) [-16]))) (SBBLcarrymask (CMP(Q|L)const (NEG(Q|L) (ADD(Q|L)const (AND(Q|L)const y [15]) [-16])) [16])))) && v.Type.Size() == 2 => (ROLW x y) (ORL (SHRW x (AND(Q|L)const y [15])) (SHLL x (NEG(Q|L) (ADD(Q|L)const (AND(Q|L)const y [15]) [-16])))) && v.Type.Size() == 2 => (RORW x y) (ORL (SHLL x (AND(Q|L)const y [ 7])) (ANDL (SHRB x (NEG(Q|L) (ADD(Q|L)const (AND(Q|L)const y [ 7]) [ -8]))) (SBBLcarrymask (CMP(Q|L)const (NEG(Q|L) (ADD(Q|L)const (AND(Q|L)const y [ 7]) [ -8])) [ 8])))) && v.Type.Size() == 1 => (ROLB x y) (ORL (SHRB x (AND(Q|L)const y [ 7])) (SHLL x (NEG(Q|L) (ADD(Q|L)const (AND(Q|L)const y [ 7]) [ -8])))) && v.Type.Size() == 1 => (RORB x y) // rotate left negative = rotate right (ROLQ x (NEG(Q|L) y)) => (RORQ x y) (ROLL x (NEG(Q|L) y)) => (RORL x y) (ROLW x (NEG(Q|L) y)) => (RORW x y) (ROLB x (NEG(Q|L) y)) => (RORB x y) // rotate right negative = rotate left (RORQ x (NEG(Q|L) y)) => (ROLQ x y) (RORL x (NEG(Q|L) y)) => (ROLL x y) (RORW x (NEG(Q|L) y)) => (ROLW x y) (RORB x (NEG(Q|L) y)) => (ROLB x y) // rotate by constants (ROLQ x (MOV(Q|L)const [c])) => (ROLQconst [int8(c&63)] x) (ROLL x (MOV(Q|L)const [c])) => (ROLLconst [int8(c&31)] x) (ROLW x (MOV(Q|L)const [c])) => (ROLWconst [int8(c&15)] x) (ROLB x (MOV(Q|L)const [c])) => (ROLBconst [int8(c&7) ] x) (RORQ x (MOV(Q|L)const [c])) => (ROLQconst [int8((-c)&63)] x) (RORL x (MOV(Q|L)const [c])) => (ROLLconst [int8((-c)&31)] x) (RORW x (MOV(Q|L)const [c])) => (ROLWconst [int8((-c)&15)] x) (RORB x (MOV(Q|L)const [c])) => (ROLBconst [int8((-c)&7) ] x) // Constant shift simplifications ((SHLQ|SHRQ|SARQ)const x [0]) => x ((SHLL|SHRL|SARL)const x [0]) => x ((SHRW|SARW)const x [0]) => x ((SHRB|SARB)const x [0]) => x ((ROLQ|ROLL|ROLW|ROLB)const x [0]) => x // Multi-register shifts (ORQ (SH(R|L)Q lo bits) (SH(L|R)Q hi (NEGQ bits))) => (SH(R|L)DQ lo hi bits) // Note: the word and byte shifts keep the low 5 bits (not the low 4 or 3 bits) // because the x86 instructions are defined to use all 5 bits of the shift even // for the small shifts. I don't think we'll ever generate a weird shift (e.g. // (SHRW x (MOVLconst [24])), but just in case. (CMPQ x (MOVQconst [c])) && is32Bit(c) => (CMPQconst x [int32(c)]) (CMPQ (MOVQconst [c]) x) && is32Bit(c) => (InvertFlags (CMPQconst x [int32(c)])) (CMPL x (MOVLconst [c])) => (CMPLconst x [c]) (CMPL (MOVLconst [c]) x) => (InvertFlags (CMPLconst x [c])) (CMPW x (MOVLconst [c])) => (CMPWconst x [int16(c)]) (CMPW (MOVLconst [c]) x) => (InvertFlags (CMPWconst x [int16(c)])) (CMPB x (MOVLconst [c])) => (CMPBconst x [int8(c)]) (CMPB (MOVLconst [c]) x) => (InvertFlags (CMPBconst x [int8(c)])) // Canonicalize the order of arguments to comparisons - helps with CSE. (CMP(Q|L|W|B) x y) && canonLessThan(x,y) => (InvertFlags (CMP(Q|L|W|B) y x)) // Using MOVZX instead of AND is cheaper. (AND(Q|L)const [ 0xFF] x) => (MOVBQZX x) (AND(Q|L)const [0xFFFF] x) => (MOVWQZX x) // This rule is currently invalid because 0xFFFFFFFF is not representable by a signed int32. // Commenting out for now, because it also can't trigger because of the is32bit guard on the // ANDQconst lowering-rule, above, prevents 0xFFFFFFFF from matching (for the same reason) // Using an alternate form of this rule segfaults some binaries because of // adverse interactions with other passes. // (ANDQconst [0xFFFFFFFF] x) => (MOVLQZX x) // strength reduction // Assumes that the following costs from https://gmplib.org/~tege/x86-timing.pdf: // 1 - addq, shlq, leaq, negq, subq // 3 - imulq // This limits the rewrites to two instructions. // Note that negq always operates in-place, // which can require a register-register move // to preserve the original value, // so it must be used with care. (MUL(Q|L)const [-9] x) => (NEG(Q|L) (LEA(Q|L)8 x x)) (MUL(Q|L)const [-5] x) => (NEG(Q|L) (LEA(Q|L)4 x x)) (MUL(Q|L)const [-3] x) => (NEG(Q|L) (LEA(Q|L)2 x x)) (MUL(Q|L)const [-1] x) => (NEG(Q|L) x) (MUL(Q|L)const [ 0] _) => (MOV(Q|L)const [0]) (MUL(Q|L)const [ 1] x) => x (MUL(Q|L)const [ 3] x) => (LEA(Q|L)2 x x) (MUL(Q|L)const [ 5] x) => (LEA(Q|L)4 x x) (MUL(Q|L)const [ 7] x) => (LEA(Q|L)2 x (LEA(Q|L)2 x x)) (MUL(Q|L)const [ 9] x) => (LEA(Q|L)8 x x) (MUL(Q|L)const [11] x) => (LEA(Q|L)2 x (LEA(Q|L)4 x x)) (MUL(Q|L)const [13] x) => (LEA(Q|L)4 x (LEA(Q|L)2 x x)) (MUL(Q|L)const [19] x) => (LEA(Q|L)2 x (LEA(Q|L)8 x x)) (MUL(Q|L)const [21] x) => (LEA(Q|L)4 x (LEA(Q|L)4 x x)) (MUL(Q|L)const [25] x) => (LEA(Q|L)8 x (LEA(Q|L)2 x x)) (MUL(Q|L)const [27] x) => (LEA(Q|L)8 (LEA(Q|L)2 x x) (LEA(Q|L)2 x x)) (MUL(Q|L)const [37] x) => (LEA(Q|L)4 x (LEA(Q|L)8 x x)) (MUL(Q|L)const [41] x) => (LEA(Q|L)8 x (LEA(Q|L)4 x x)) (MUL(Q|L)const [45] x) => (LEA(Q|L)8 (LEA(Q|L)4 x x) (LEA(Q|L)4 x x)) (MUL(Q|L)const [73] x) => (LEA(Q|L)8 x (LEA(Q|L)8 x x)) (MUL(Q|L)const [81] x) => (LEA(Q|L)8 (LEA(Q|L)8 x x) (LEA(Q|L)8 x x)) (MUL(Q|L)const [c] x) && isPowerOfTwo64(int64(c)+1) && c >= 15 => (SUB(Q|L) (SHL(Q|L)const [int8(log64(int64(c)+1))] x) x) (MUL(Q|L)const [c] x) && isPowerOfTwo32(c-1) && c >= 17 => (LEA(Q|L)1 (SHL(Q|L)const [int8(log32(c-1))] x) x) (MUL(Q|L)const [c] x) && isPowerOfTwo32(c-2) && c >= 34 => (LEA(Q|L)2 (SHL(Q|L)const [int8(log32(c-2))] x) x) (MUL(Q|L)const [c] x) && isPowerOfTwo32(c-4) && c >= 68 => (LEA(Q|L)4 (SHL(Q|L)const [int8(log32(c-4))] x) x) (MUL(Q|L)const [c] x) && isPowerOfTwo32(c-8) && c >= 136 => (LEA(Q|L)8 (SHL(Q|L)const [int8(log32(c-8))] x) x) (MUL(Q|L)const [c] x) && c%3 == 0 && isPowerOfTwo32(c/3) => (SHL(Q|L)const [int8(log32(c/3))] (LEA(Q|L)2 x x)) (MUL(Q|L)const [c] x) && c%5 == 0 && isPowerOfTwo32(c/5) => (SHL(Q|L)const [int8(log32(c/5))] (LEA(Q|L)4 x x)) (MUL(Q|L)const [c] x) && c%9 == 0 && isPowerOfTwo32(c/9) => (SHL(Q|L)const [int8(log32(c/9))] (LEA(Q|L)8 x x)) // combine add/shift into LEAQ/LEAL (ADD(L|Q) x (SHL(L|Q)const [3] y)) => (LEA(L|Q)8 x y) (ADD(L|Q) x (SHL(L|Q)const [2] y)) => (LEA(L|Q)4 x y) (ADD(L|Q) x (SHL(L|Q)const [1] y)) => (LEA(L|Q)2 x y) (ADD(L|Q) x (ADD(L|Q) y y)) => (LEA(L|Q)2 x y) (ADD(L|Q) x (ADD(L|Q) x y)) => (LEA(L|Q)2 y x) // combine ADDQ/ADDQconst into LEAQ1/LEAL1 (ADD(Q|L)const [c] (ADD(Q|L) x y)) => (LEA(Q|L)1 [c] x y) (ADD(Q|L) (ADD(Q|L)const [c] x) y) => (LEA(Q|L)1 [c] x y) (ADD(Q|L)const [c] (SHL(Q|L)const [1] x)) => (LEA(Q|L)1 [c] x x) // fold ADDQ/ADDL into LEAQ/LEAL (ADD(Q|L)const [c] (LEA(Q|L) [d] {s} x)) && is32Bit(int64(c)+int64(d)) => (LEA(Q|L) [c+d] {s} x) (LEA(Q|L) [c] {s} (ADD(Q|L)const [d] x)) && is32Bit(int64(c)+int64(d)) => (LEA(Q|L) [c+d] {s} x) (LEA(Q|L) [c] {s} (ADD(Q|L) x y)) && x.Op != OpSB && y.Op != OpSB => (LEA(Q|L)1 [c] {s} x y) (ADD(Q|L) x (LEA(Q|L) [c] {s} y)) && x.Op != OpSB && y.Op != OpSB => (LEA(Q|L)1 [c] {s} x y) // fold ADDQconst/ADDLconst into LEAQx/LEALx (ADD(Q|L)const [c] (LEA(Q|L)1 [d] {s} x y)) && is32Bit(int64(c)+int64(d)) => (LEA(Q|L)1 [c+d] {s} x y) (ADD(Q|L)const [c] (LEA(Q|L)2 [d] {s} x y)) && is32Bit(int64(c)+int64(d)) => (LEA(Q|L)2 [c+d] {s} x y) (ADD(Q|L)const [c] (LEA(Q|L)4 [d] {s} x y)) && is32Bit(int64(c)+int64(d)) => (LEA(Q|L)4 [c+d] {s} x y) (ADD(Q|L)const [c] (LEA(Q|L)8 [d] {s} x y)) && is32Bit(int64(c)+int64(d)) => (LEA(Q|L)8 [c+d] {s} x y) (LEA(Q|L)1 [c] {s} (ADD(Q|L)const [d] x) y) && is32Bit(int64(c)+int64(d)) && x.Op != OpSB => (LEA(Q|L)1 [c+d] {s} x y) (LEA(Q|L)2 [c] {s} (ADD(Q|L)const [d] x) y) && is32Bit(int64(c)+int64(d)) && x.Op != OpSB => (LEA(Q|L)2 [c+d] {s} x y) (LEA(Q|L)2 [c] {s} x (ADD(Q|L)const [d] y)) && is32Bit(int64(c)+2*int64(d)) && y.Op != OpSB => (LEA(Q|L)2 [c+2*d] {s} x y) (LEA(Q|L)4 [c] {s} (ADD(Q|L)const [d] x) y) && is32Bit(int64(c)+int64(d)) && x.Op != OpSB => (LEA(Q|L)4 [c+d] {s} x y) (LEA(Q|L)4 [c] {s} x (ADD(Q|L)const [d] y)) && is32Bit(int64(c)+4*int64(d)) && y.Op != OpSB => (LEA(Q|L)4 [c+4*d] {s} x y) (LEA(Q|L)8 [c] {s} (ADD(Q|L)const [d] x) y) && is32Bit(int64(c)+int64(d)) && x.Op != OpSB => (LEA(Q|L)8 [c+d] {s} x y) (LEA(Q|L)8 [c] {s} x (ADD(Q|L)const [d] y)) && is32Bit(int64(c)+8*int64(d)) && y.Op != OpSB => (LEA(Q|L)8 [c+8*d] {s} x y) // fold shifts into LEAQx/LEALx (LEA(Q|L)1 [c] {s} x (SHL(Q|L)const [1] y)) => (LEA(Q|L)2 [c] {s} x y) (LEA(Q|L)1 [c] {s} x (SHL(Q|L)const [2] y)) => (LEA(Q|L)4 [c] {s} x y) (LEA(Q|L)1 [c] {s} x (SHL(Q|L)const [3] y)) => (LEA(Q|L)8 [c] {s} x y) (LEA(Q|L)2 [c] {s} x (SHL(Q|L)const [1] y)) => (LEA(Q|L)4 [c] {s} x y) (LEA(Q|L)2 [c] {s} x (SHL(Q|L)const [2] y)) => (LEA(Q|L)8 [c] {s} x y) (LEA(Q|L)4 [c] {s} x (SHL(Q|L)const [1] y)) => (LEA(Q|L)8 [c] {s} x y) // reverse ordering of compare instruction (SETL (InvertFlags x)) => (SETG x) (SETG (InvertFlags x)) => (SETL x) (SETB (InvertFlags x)) => (SETA x) (SETA (InvertFlags x)) => (SETB x) (SETLE (InvertFlags x)) => (SETGE x) (SETGE (InvertFlags x)) => (SETLE x) (SETBE (InvertFlags x)) => (SETAE x) (SETAE (InvertFlags x)) => (SETBE x) (SETEQ (InvertFlags x)) => (SETEQ x) (SETNE (InvertFlags x)) => (SETNE x) (SETLstore [off] {sym} ptr (InvertFlags x) mem) => (SETGstore [off] {sym} ptr x mem) (SETGstore [off] {sym} ptr (InvertFlags x) mem) => (SETLstore [off] {sym} ptr x mem) (SETBstore [off] {sym} ptr (InvertFlags x) mem) => (SETAstore [off] {sym} ptr x mem) (SETAstore [off] {sym} ptr (InvertFlags x) mem) => (SETBstore [off] {sym} ptr x mem) (SETLEstore [off] {sym} ptr (InvertFlags x) mem) => (SETGEstore [off] {sym} ptr x mem) (SETGEstore [off] {sym} ptr (InvertFlags x) mem) => (SETLEstore [off] {sym} ptr x mem) (SETBEstore [off] {sym} ptr (InvertFlags x) mem) => (SETAEstore [off] {sym} ptr x mem) (SETAEstore [off] {sym} ptr (InvertFlags x) mem) => (SETBEstore [off] {sym} ptr x mem) (SETEQstore [off] {sym} ptr (InvertFlags x) mem) => (SETEQstore [off] {sym} ptr x mem) (SETNEstore [off] {sym} ptr (InvertFlags x) mem) => (SETNEstore [off] {sym} ptr x mem) // sign extended loads // Note: The combined instruction must end up in the same block // as the original load. If not, we end up making a value with // memory type live in two different blocks, which can lead to // multiple memory values alive simultaneously. // Make sure we don't combine these ops if the load has another use. // This prevents a single load from being split into multiple loads // which then might return different values. See test/atomicload.go. (MOVBQSX x:(MOVBload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBQSXload [off] {sym} ptr mem) (MOVBQSX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBQSXload [off] {sym} ptr mem) (MOVBQSX x:(MOVLload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBQSXload [off] {sym} ptr mem) (MOVBQSX x:(MOVQload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBQSXload [off] {sym} ptr mem) (MOVBQZX x:(MOVBload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBload [off] {sym} ptr mem) (MOVBQZX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBload [off] {sym} ptr mem) (MOVBQZX x:(MOVLload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBload [off] {sym} ptr mem) (MOVBQZX x:(MOVQload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBload [off] {sym} ptr mem) (MOVWQSX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVWQSXload [off] {sym} ptr mem) (MOVWQSX x:(MOVLload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVWQSXload [off] {sym} ptr mem) (MOVWQSX x:(MOVQload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVWQSXload [off] {sym} ptr mem) (MOVWQZX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVWload [off] {sym} ptr mem) (MOVWQZX x:(MOVLload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVWload [off] {sym} ptr mem) (MOVWQZX x:(MOVQload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVWload [off] {sym} ptr mem) (MOVLQSX x:(MOVLload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVLQSXload [off] {sym} ptr mem) (MOVLQSX x:(MOVQload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVLQSXload [off] {sym} ptr mem) (MOVLQZX x:(MOVLload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVLload [off] {sym} ptr mem) (MOVLQZX x:(MOVQload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVLload [off] {sym} ptr mem) (MOVLQZX x) && zeroUpper32Bits(x,3) => x (MOVWQZX x) && zeroUpper48Bits(x,3) => x (MOVBQZX x) && zeroUpper56Bits(x,3) => x // replace load from same location as preceding store with zero/sign extension (or copy in case of full width) (MOVBload [off] {sym} ptr (MOVBstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) => (MOVBQZX x) (MOVWload [off] {sym} ptr (MOVWstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) => (MOVWQZX x) (MOVLload [off] {sym} ptr (MOVLstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) => (MOVLQZX x) (MOVQload [off] {sym} ptr (MOVQstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) => x (MOVBQSXload [off] {sym} ptr (MOVBstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) => (MOVBQSX x) (MOVWQSXload [off] {sym} ptr (MOVWstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) => (MOVWQSX x) (MOVLQSXload [off] {sym} ptr (MOVLstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) => (MOVLQSX x) // Fold extensions and ANDs together. (MOVBQZX (ANDLconst [c] x)) => (ANDLconst [c & 0xff] x) (MOVWQZX (ANDLconst [c] x)) => (ANDLconst [c & 0xffff] x) (MOVLQZX (ANDLconst [c] x)) => (ANDLconst [c] x) (MOVBQSX (ANDLconst [c] x)) && c & 0x80 == 0 => (ANDLconst [c & 0x7f] x) (MOVWQSX (ANDLconst [c] x)) && c & 0x8000 == 0 => (ANDLconst [c & 0x7fff] x) (MOVLQSX (ANDLconst [c] x)) && uint32(c) & 0x80000000 == 0 => (ANDLconst [c & 0x7fffffff] x) // Don't extend before storing (MOVLstore [off] {sym} ptr (MOVLQSX x) mem) => (MOVLstore [off] {sym} ptr x mem) (MOVWstore [off] {sym} ptr (MOVWQSX x) mem) => (MOVWstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr (MOVBQSX x) mem) => (MOVBstore [off] {sym} ptr x mem) (MOVLstore [off] {sym} ptr (MOVLQZX x) mem) => (MOVLstore [off] {sym} ptr x mem) (MOVWstore [off] {sym} ptr (MOVWQZX x) mem) => (MOVWstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr (MOVBQZX x) mem) => (MOVBstore [off] {sym} ptr x mem) // fold constants into memory operations // Note that this is not always a good idea because if not all the uses of // the ADDQconst get eliminated, we still have to compute the ADDQconst and we now // have potentially two live values (ptr and (ADDQconst [off] ptr)) instead of one. // Nevertheless, let's do it! (MOV(Q|L|W|B|SS|SD|O)load [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(int64(off1)+int64(off2)) => (MOV(Q|L|W|B|SS|SD|O)load [off1+off2] {sym} ptr mem) (MOV(Q|L|W|B|SS|SD|O)store [off1] {sym} (ADDQconst [off2] ptr) val mem) && is32Bit(int64(off1)+int64(off2)) => (MOV(Q|L|W|B|SS|SD|O)store [off1+off2] {sym} ptr val mem) (SET(L|G|B|A|LE|GE|BE|AE|EQ|NE)store [off1] {sym} (ADDQconst [off2] base) val mem) && is32Bit(int64(off1)+int64(off2)) => (SET(L|G|B|A|LE|GE|BE|AE|EQ|NE)store [off1+off2] {sym} base val mem) ((ADD|SUB|AND|OR|XOR)Qload [off1] {sym} val (ADDQconst [off2] base) mem) && is32Bit(int64(off1)+int64(off2)) => ((ADD|SUB|AND|OR|XOR)Qload [off1+off2] {sym} val base mem) ((ADD|SUB|AND|OR|XOR)Lload [off1] {sym} val (ADDQconst [off2] base) mem) && is32Bit(int64(off1)+int64(off2)) => ((ADD|SUB|AND|OR|XOR)Lload [off1+off2] {sym} val base mem) (CMP(Q|L|W|B)load [off1] {sym} (ADDQconst [off2] base) val mem) && is32Bit(int64(off1)+int64(off2)) => (CMP(Q|L|W|B)load [off1+off2] {sym} base val mem) (CMP(Q|L|W|B)constload [valoff1] {sym} (ADDQconst [off2] base) mem) && ValAndOff(valoff1).canAdd32(off2) => (CMP(Q|L|W|B)constload [ValAndOff(valoff1).addOffset32(off2)] {sym} base mem) ((ADD|SUB|MUL|DIV)SSload [off1] {sym} val (ADDQconst [off2] base) mem) && is32Bit(int64(off1)+int64(off2)) => ((ADD|SUB|MUL|DIV)SSload [off1+off2] {sym} val base mem) ((ADD|SUB|MUL|DIV)SDload [off1] {sym} val (ADDQconst [off2] base) mem) && is32Bit(int64(off1)+int64(off2)) => ((ADD|SUB|MUL|DIV)SDload [off1+off2] {sym} val base mem) ((ADD|AND|OR|XOR)Qconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) && ValAndOff(valoff1).canAdd32(off2) => ((ADD|AND|OR|XOR)Qconstmodify [ValAndOff(valoff1).addOffset32(off2)] {sym} base mem) ((ADD|AND|OR|XOR)Lconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) && ValAndOff(valoff1).canAdd32(off2) => ((ADD|AND|OR|XOR)Lconstmodify [ValAndOff(valoff1).addOffset32(off2)] {sym} base mem) ((ADD|SUB|AND|OR|XOR)Qmodify [off1] {sym} (ADDQconst [off2] base) val mem) && is32Bit(int64(off1)+int64(off2)) => ((ADD|SUB|AND|OR|XOR)Qmodify [off1+off2] {sym} base val mem) ((ADD|SUB|AND|OR|XOR)Lmodify [off1] {sym} (ADDQconst [off2] base) val mem) && is32Bit(int64(off1)+int64(off2)) => ((ADD|SUB|AND|OR|XOR)Lmodify [off1+off2] {sym} base val mem) // Fold constants into stores. (MOVQstore [off] {sym} ptr (MOVQconst [c]) mem) && validVal(c) => (MOVQstoreconst [makeValAndOff(int32(c),off)] {sym} ptr mem) (MOVLstore [off] {sym} ptr (MOV(L|Q)const [c]) mem) => (MOVLstoreconst [makeValAndOff(int32(c),off)] {sym} ptr mem) (MOVWstore [off] {sym} ptr (MOV(L|Q)const [c]) mem) => (MOVWstoreconst [makeValAndOff(int32(int16(c)),off)] {sym} ptr mem) (MOVBstore [off] {sym} ptr (MOV(L|Q)const [c]) mem) => (MOVBstoreconst [makeValAndOff(int32(int8(c)),off)] {sym} ptr mem) // Fold address offsets into constant stores. (MOV(Q|L|W|B|O)storeconst [sc] {s} (ADDQconst [off] ptr) mem) && ValAndOff(sc).canAdd32(off) => (MOV(Q|L|W|B|O)storeconst [ValAndOff(sc).addOffset32(off)] {s} ptr mem) // We need to fold LEAQ into the MOVx ops so that the live variable analysis knows // what variables are being read/written by the ops. (MOV(Q|L|W|B|SS|SD|O|BQSX|WQSX|LQSX)load [off1] {sym1} (LEAQ [off2] {sym2} base) mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (MOV(Q|L|W|B|SS|SD|O|BQSX|WQSX|LQSX)load [off1+off2] {mergeSym(sym1,sym2)} base mem) (MOV(Q|L|W|B|SS|SD|O)store [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (MOV(Q|L|W|B|SS|SD|O)store [off1+off2] {mergeSym(sym1,sym2)} base val mem) (MOV(Q|L|W|B|O)storeconst [sc] {sym1} (LEAQ [off] {sym2} ptr) mem) && canMergeSym(sym1, sym2) && ValAndOff(sc).canAdd32(off) => (MOV(Q|L|W|B|O)storeconst [ValAndOff(sc).addOffset32(off)] {mergeSym(sym1, sym2)} ptr mem) (SET(L|G|B|A|LE|GE|BE|AE|EQ|NE)store [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (SET(L|G|B|A|LE|GE|BE|AE|EQ|NE)store [off1+off2] {mergeSym(sym1,sym2)} base val mem) ((ADD|SUB|AND|OR|XOR)Qload [off1] {sym1} val (LEAQ [off2] {sym2} base) mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => ((ADD|SUB|AND|OR|XOR)Qload [off1+off2] {mergeSym(sym1,sym2)} val base mem) ((ADD|SUB|AND|OR|XOR)Lload [off1] {sym1} val (LEAQ [off2] {sym2} base) mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => ((ADD|SUB|AND|OR|XOR)Lload [off1+off2] {mergeSym(sym1,sym2)} val base mem) (CMP(Q|L|W|B)load [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (CMP(Q|L|W|B)load [off1+off2] {mergeSym(sym1,sym2)} base val mem) (CMP(Q|L|W|B)constload [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) && ValAndOff(valoff1).canAdd32(off2) && canMergeSym(sym1, sym2) => (CMP(Q|L|W|B)constload [ValAndOff(valoff1).addOffset32(off2)] {mergeSym(sym1,sym2)} base mem) ((ADD|SUB|MUL|DIV)SSload [off1] {sym1} val (LEAQ [off2] {sym2} base) mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => ((ADD|SUB|MUL|DIV)SSload [off1+off2] {mergeSym(sym1,sym2)} val base mem) ((ADD|SUB|MUL|DIV)SDload [off1] {sym1} val (LEAQ [off2] {sym2} base) mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => ((ADD|SUB|MUL|DIV)SDload [off1+off2] {mergeSym(sym1,sym2)} val base mem) ((ADD|AND|OR|XOR)Qconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) && ValAndOff(valoff1).canAdd32(off2) && canMergeSym(sym1, sym2) => ((ADD|AND|OR|XOR)Qconstmodify [ValAndOff(valoff1).addOffset32(off2)] {mergeSym(sym1,sym2)} base mem) ((ADD|AND|OR|XOR)Lconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) && ValAndOff(valoff1).canAdd32(off2) && canMergeSym(sym1, sym2) => ((ADD|AND|OR|XOR)Lconstmodify [ValAndOff(valoff1).addOffset32(off2)] {mergeSym(sym1,sym2)} base mem) ((ADD|SUB|AND|OR|XOR)Qmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => ((ADD|SUB|AND|OR|XOR)Qmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) ((ADD|SUB|AND|OR|XOR)Lmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => ((ADD|SUB|AND|OR|XOR)Lmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) // fold LEAQs together (LEAQ [off1] {sym1} (LEAQ [off2] {sym2} x)) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (LEAQ [off1+off2] {mergeSym(sym1,sym2)} x) // LEAQ into LEAQ1 (LEAQ1 [off1] {sym1} (LEAQ [off2] {sym2} x) y) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) && x.Op != OpSB => (LEAQ1 [off1+off2] {mergeSym(sym1,sym2)} x y) // LEAQ1 into LEAQ (LEAQ [off1] {sym1} (LEAQ1 [off2] {sym2} x y)) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (LEAQ1 [off1+off2] {mergeSym(sym1,sym2)} x y) // LEAQ into LEAQ[248] (LEAQ2 [off1] {sym1} (LEAQ [off2] {sym2} x) y) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) && x.Op != OpSB => (LEAQ2 [off1+off2] {mergeSym(sym1,sym2)} x y) (LEAQ4 [off1] {sym1} (LEAQ [off2] {sym2} x) y) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) && x.Op != OpSB => (LEAQ4 [off1+off2] {mergeSym(sym1,sym2)} x y) (LEAQ8 [off1] {sym1} (LEAQ [off2] {sym2} x) y) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) && x.Op != OpSB => (LEAQ8 [off1+off2] {mergeSym(sym1,sym2)} x y) // LEAQ[248] into LEAQ (LEAQ [off1] {sym1} (LEAQ2 [off2] {sym2} x y)) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (LEAQ2 [off1+off2] {mergeSym(sym1,sym2)} x y) (LEAQ [off1] {sym1} (LEAQ4 [off2] {sym2} x y)) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (LEAQ4 [off1+off2] {mergeSym(sym1,sym2)} x y) (LEAQ [off1] {sym1} (LEAQ8 [off2] {sym2} x y)) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (LEAQ8 [off1+off2] {mergeSym(sym1,sym2)} x y) // LEAQ[1248] into LEAQ[1248]. Only some such merges are possible. (LEAQ1 [off1] {sym1} x (LEAQ1 [off2] {sym2} y y)) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (LEAQ2 [off1+off2] {mergeSym(sym1, sym2)} x y) (LEAQ1 [off1] {sym1} x (LEAQ1 [off2] {sym2} x y)) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (LEAQ2 [off1+off2] {mergeSym(sym1, sym2)} y x) (LEAQ2 [off1] {sym1} x (LEAQ1 [off2] {sym2} y y)) && is32Bit(int64(off1)+2*int64(off2)) && sym2 == nil => (LEAQ4 [off1+2*off2] {sym1} x y) (LEAQ4 [off1] {sym1} x (LEAQ1 [off2] {sym2} y y)) && is32Bit(int64(off1)+4*int64(off2)) && sym2 == nil => (LEAQ8 [off1+4*off2] {sym1} x y) // TODO: more? // Lower LEAQ2/4/8 when the offset is a constant (LEAQ2 [off] {sym} x (MOV(Q|L)const [scale])) && is32Bit(int64(off)+int64(scale)*2) => (LEAQ [off+int32(scale)*2] {sym} x) (LEAQ4 [off] {sym} x (MOV(Q|L)const [scale])) && is32Bit(int64(off)+int64(scale)*4) => (LEAQ [off+int32(scale)*4] {sym} x) (LEAQ8 [off] {sym} x (MOV(Q|L)const [scale])) && is32Bit(int64(off)+int64(scale)*8) => (LEAQ [off+int32(scale)*8] {sym} x) // Absorb InvertFlags into branches. (LT (InvertFlags cmp) yes no) => (GT cmp yes no) (GT (InvertFlags cmp) yes no) => (LT cmp yes no) (LE (InvertFlags cmp) yes no) => (GE cmp yes no) (GE (InvertFlags cmp) yes no) => (LE cmp yes no) (ULT (InvertFlags cmp) yes no) => (UGT cmp yes no) (UGT (InvertFlags cmp) yes no) => (ULT cmp yes no) (ULE (InvertFlags cmp) yes no) => (UGE cmp yes no) (UGE (InvertFlags cmp) yes no) => (ULE cmp yes no) (EQ (InvertFlags cmp) yes no) => (EQ cmp yes no) (NE (InvertFlags cmp) yes no) => (NE cmp yes no) // Constant comparisons. (CMPQconst (MOVQconst [x]) [y]) && x==int64(y) => (FlagEQ) (CMPQconst (MOVQconst [x]) [y]) && x (FlagLT_ULT) (CMPQconst (MOVQconst [x]) [y]) && xuint64(int64(y)) => (FlagLT_UGT) (CMPQconst (MOVQconst [x]) [y]) && x>int64(y) && uint64(x) (FlagGT_ULT) (CMPQconst (MOVQconst [x]) [y]) && x>int64(y) && uint64(x)>uint64(int64(y)) => (FlagGT_UGT) (CMPLconst (MOVLconst [x]) [y]) && x==y => (FlagEQ) (CMPLconst (MOVLconst [x]) [y]) && x (FlagLT_ULT) (CMPLconst (MOVLconst [x]) [y]) && xuint32(y) => (FlagLT_UGT) (CMPLconst (MOVLconst [x]) [y]) && x>y && uint32(x) (FlagGT_ULT) (CMPLconst (MOVLconst [x]) [y]) && x>y && uint32(x)>uint32(y) => (FlagGT_UGT) (CMPWconst (MOVLconst [x]) [y]) && int16(x)==y => (FlagEQ) (CMPWconst (MOVLconst [x]) [y]) && int16(x) (FlagLT_ULT) (CMPWconst (MOVLconst [x]) [y]) && int16(x)uint16(y) => (FlagLT_UGT) (CMPWconst (MOVLconst [x]) [y]) && int16(x)>y && uint16(x) (FlagGT_ULT) (CMPWconst (MOVLconst [x]) [y]) && int16(x)>y && uint16(x)>uint16(y) => (FlagGT_UGT) (CMPBconst (MOVLconst [x]) [y]) && int8(x)==y => (FlagEQ) (CMPBconst (MOVLconst [x]) [y]) && int8(x) (FlagLT_ULT) (CMPBconst (MOVLconst [x]) [y]) && int8(x)uint8(y) => (FlagLT_UGT) (CMPBconst (MOVLconst [x]) [y]) && int8(x)>y && uint8(x) (FlagGT_ULT) (CMPBconst (MOVLconst [x]) [y]) && int8(x)>y && uint8(x)>uint8(y) => (FlagGT_UGT) // CMPQconst requires a 32 bit const, but we can still constant-fold 64 bit consts. // In theory this applies to any of the simplifications above, // but CMPQ is the only one I've actually seen occur. (CMPQ (MOVQconst [x]) (MOVQconst [y])) && x==y => (FlagEQ) (CMPQ (MOVQconst [x]) (MOVQconst [y])) && x (FlagLT_ULT) (CMPQ (MOVQconst [x]) (MOVQconst [y])) && xuint64(y) => (FlagLT_UGT) (CMPQ (MOVQconst [x]) (MOVQconst [y])) && x>y && uint64(x) (FlagGT_ULT) (CMPQ (MOVQconst [x]) (MOVQconst [y])) && x>y && uint64(x)>uint64(y) => (FlagGT_UGT) // Other known comparisons. (CMPQconst (MOVBQZX _) [c]) && 0xFF < c => (FlagLT_ULT) (CMPQconst (MOVWQZX _) [c]) && 0xFFFF < c => (FlagLT_ULT) (CMPLconst (SHRLconst _ [c]) [n]) && 0 <= n && 0 < c && c <= 32 && (1< (FlagLT_ULT) (CMPQconst (SHRQconst _ [c]) [n]) && 0 <= n && 0 < c && c <= 64 && (1< (FlagLT_ULT) (CMPQconst (ANDQconst _ [m]) [n]) && 0 <= m && m < n => (FlagLT_ULT) (CMPQconst (ANDLconst _ [m]) [n]) && 0 <= m && m < n => (FlagLT_ULT) (CMPLconst (ANDLconst _ [m]) [n]) && 0 <= m && m < n => (FlagLT_ULT) (CMPWconst (ANDLconst _ [m]) [n]) && 0 <= int16(m) && int16(m) < n => (FlagLT_ULT) (CMPBconst (ANDLconst _ [m]) [n]) && 0 <= int8(m) && int8(m) < n => (FlagLT_ULT) // TESTQ c c sets flags like CMPQ c 0. (TESTQconst [c] (MOVQconst [d])) && int64(c) == d && c == 0 => (FlagEQ) (TESTLconst [c] (MOVLconst [c])) && c == 0 => (FlagEQ) (TESTQconst [c] (MOVQconst [d])) && int64(c) == d && c < 0 => (FlagLT_UGT) (TESTLconst [c] (MOVLconst [c])) && c < 0 => (FlagLT_UGT) (TESTQconst [c] (MOVQconst [d])) && int64(c) == d && c > 0 => (FlagGT_UGT) (TESTLconst [c] (MOVLconst [c])) && c > 0 => (FlagGT_UGT) // TODO: DIVxU also. // Absorb flag constants into SBB ops. (SBBQcarrymask (FlagEQ)) => (MOVQconst [0]) (SBBQcarrymask (FlagLT_ULT)) => (MOVQconst [-1]) (SBBQcarrymask (FlagLT_UGT)) => (MOVQconst [0]) (SBBQcarrymask (FlagGT_ULT)) => (MOVQconst [-1]) (SBBQcarrymask (FlagGT_UGT)) => (MOVQconst [0]) (SBBLcarrymask (FlagEQ)) => (MOVLconst [0]) (SBBLcarrymask (FlagLT_ULT)) => (MOVLconst [-1]) (SBBLcarrymask (FlagLT_UGT)) => (MOVLconst [0]) (SBBLcarrymask (FlagGT_ULT)) => (MOVLconst [-1]) (SBBLcarrymask (FlagGT_UGT)) => (MOVLconst [0]) // Absorb flag constants into branches. ((EQ|LE|GE|ULE|UGE) (FlagEQ) yes no) => (First yes no) ((NE|LT|GT|ULT|UGT) (FlagEQ) yes no) => (First no yes) ((NE|LT|LE|ULT|ULE) (FlagLT_ULT) yes no) => (First yes no) ((EQ|GT|GE|UGT|UGE) (FlagLT_ULT) yes no) => (First no yes) ((NE|LT|LE|UGT|UGE) (FlagLT_UGT) yes no) => (First yes no) ((EQ|GT|GE|ULT|ULE) (FlagLT_UGT) yes no) => (First no yes) ((NE|GT|GE|ULT|ULE) (FlagGT_ULT) yes no) => (First yes no) ((EQ|LT|LE|UGT|UGE) (FlagGT_ULT) yes no) => (First no yes) ((NE|GT|GE|UGT|UGE) (FlagGT_UGT) yes no) => (First yes no) ((EQ|LT|LE|ULT|ULE) (FlagGT_UGT) yes no) => (First no yes) // Absorb flag constants into SETxx ops. ((SETEQ|SETLE|SETGE|SETBE|SETAE) (FlagEQ)) => (MOVLconst [1]) ((SETNE|SETL|SETG|SETB|SETA) (FlagEQ)) => (MOVLconst [0]) ((SETNE|SETL|SETLE|SETB|SETBE) (FlagLT_ULT)) => (MOVLconst [1]) ((SETEQ|SETG|SETGE|SETA|SETAE) (FlagLT_ULT)) => (MOVLconst [0]) ((SETNE|SETL|SETLE|SETA|SETAE) (FlagLT_UGT)) => (MOVLconst [1]) ((SETEQ|SETG|SETGE|SETB|SETBE) (FlagLT_UGT)) => (MOVLconst [0]) ((SETNE|SETG|SETGE|SETB|SETBE) (FlagGT_ULT)) => (MOVLconst [1]) ((SETEQ|SETL|SETLE|SETA|SETAE) (FlagGT_ULT)) => (MOVLconst [0]) ((SETNE|SETG|SETGE|SETA|SETAE) (FlagGT_UGT)) => (MOVLconst [1]) ((SETEQ|SETL|SETLE|SETB|SETBE) (FlagGT_UGT)) => (MOVLconst [0]) (SETEQstore [off] {sym} ptr (FlagEQ) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETEQstore [off] {sym} ptr (FlagLT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETEQstore [off] {sym} ptr (FlagLT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETEQstore [off] {sym} ptr (FlagGT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETEQstore [off] {sym} ptr (FlagGT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETNEstore [off] {sym} ptr (FlagEQ) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETNEstore [off] {sym} ptr (FlagLT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETNEstore [off] {sym} ptr (FlagLT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETNEstore [off] {sym} ptr (FlagGT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETNEstore [off] {sym} ptr (FlagGT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETLstore [off] {sym} ptr (FlagEQ) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETLstore [off] {sym} ptr (FlagLT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETLstore [off] {sym} ptr (FlagLT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETLstore [off] {sym} ptr (FlagGT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETLstore [off] {sym} ptr (FlagGT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETLEstore [off] {sym} ptr (FlagEQ) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETLEstore [off] {sym} ptr (FlagLT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETLEstore [off] {sym} ptr (FlagLT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETLEstore [off] {sym} ptr (FlagGT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETLEstore [off] {sym} ptr (FlagGT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETGstore [off] {sym} ptr (FlagEQ) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETGstore [off] {sym} ptr (FlagLT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETGstore [off] {sym} ptr (FlagLT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETGstore [off] {sym} ptr (FlagGT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETGstore [off] {sym} ptr (FlagGT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETGEstore [off] {sym} ptr (FlagEQ) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETGEstore [off] {sym} ptr (FlagLT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETGEstore [off] {sym} ptr (FlagLT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETGEstore [off] {sym} ptr (FlagGT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETGEstore [off] {sym} ptr (FlagGT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETBstore [off] {sym} ptr (FlagEQ) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETBstore [off] {sym} ptr (FlagLT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETBstore [off] {sym} ptr (FlagLT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETBstore [off] {sym} ptr (FlagGT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETBstore [off] {sym} ptr (FlagGT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETBEstore [off] {sym} ptr (FlagEQ) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETBEstore [off] {sym} ptr (FlagLT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETBEstore [off] {sym} ptr (FlagLT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETBEstore [off] {sym} ptr (FlagGT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETBEstore [off] {sym} ptr (FlagGT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETAstore [off] {sym} ptr (FlagEQ) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETAstore [off] {sym} ptr (FlagLT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETAstore [off] {sym} ptr (FlagLT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETAstore [off] {sym} ptr (FlagGT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETAstore [off] {sym} ptr (FlagGT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETAEstore [off] {sym} ptr (FlagEQ) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETAEstore [off] {sym} ptr (FlagLT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETAEstore [off] {sym} ptr (FlagLT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) (SETAEstore [off] {sym} ptr (FlagGT_ULT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [0]) mem) (SETAEstore [off] {sym} ptr (FlagGT_UGT) mem) => (MOVBstore [off] {sym} ptr (MOVLconst [1]) mem) // Remove redundant *const ops (ADDQconst [0] x) => x (ADDLconst [c] x) && c==0 => x (SUBQconst [0] x) => x (SUBLconst [c] x) && c==0 => x (ANDQconst [0] _) => (MOVQconst [0]) (ANDLconst [c] _) && c==0 => (MOVLconst [0]) (ANDQconst [-1] x) => x (ANDLconst [c] x) && c==-1 => x (ORQconst [0] x) => x (ORLconst [c] x) && c==0 => x (ORQconst [-1] _) => (MOVQconst [-1]) (ORLconst [c] _) && c==-1 => (MOVLconst [-1]) (XORQconst [0] x) => x (XORLconst [c] x) && c==0 => x // TODO: since we got rid of the W/B versions, we might miss // things like (ANDLconst [0x100] x) which were formerly // (ANDBconst [0] x). Probably doesn't happen very often. // If we cared, we might do: // (ANDLconst [c] x) && t.Size()==1 && int8(x)==0 -> (MOVLconst [0]) // Remove redundant ops // Not in generic rules, because they may appear after lowering e. g. Slicemask (NEG(Q|L) (NEG(Q|L) x)) => x (NEG(Q|L) s:(SUB(Q|L) x y)) && s.Uses == 1 => (SUB(Q|L) y x) // Convert constant subtracts to constant adds (SUBQconst [c] x) && c != -(1<<31) => (ADDQconst [-c] x) (SUBLconst [c] x) => (ADDLconst [-c] x) // generic constant folding // TODO: more of this (ADDQconst [c] (MOVQconst [d])) => (MOVQconst [int64(c)+d]) (ADDLconst [c] (MOVLconst [d])) => (MOVLconst [c+d]) (ADDQconst [c] (ADDQconst [d] x)) && is32Bit(int64(c)+int64(d)) => (ADDQconst [c+d] x) (ADDLconst [c] (ADDLconst [d] x)) => (ADDLconst [c+d] x) (SUBQconst (MOVQconst [d]) [c]) => (MOVQconst [d-int64(c)]) (SUBQconst (SUBQconst x [d]) [c]) && is32Bit(int64(-c)-int64(d)) => (ADDQconst [-c-d] x) (SARQconst [c] (MOVQconst [d])) => (MOVQconst [d>>uint64(c)]) (SARLconst [c] (MOVQconst [d])) => (MOVQconst [int64(int32(d))>>uint64(c)]) (SARWconst [c] (MOVQconst [d])) => (MOVQconst [int64(int16(d))>>uint64(c)]) (SARBconst [c] (MOVQconst [d])) => (MOVQconst [int64(int8(d))>>uint64(c)]) (NEGQ (MOVQconst [c])) => (MOVQconst [-c]) (NEGL (MOVLconst [c])) => (MOVLconst [-c]) (MULQconst [c] (MOVQconst [d])) => (MOVQconst [int64(c)*d]) (MULLconst [c] (MOVLconst [d])) => (MOVLconst [c*d]) (ANDQconst [c] (MOVQconst [d])) => (MOVQconst [int64(c)&d]) (ANDLconst [c] (MOVLconst [d])) => (MOVLconst [c&d]) (ORQconst [c] (MOVQconst [d])) => (MOVQconst [int64(c)|d]) (ORLconst [c] (MOVLconst [d])) => (MOVLconst [c|d]) (XORQconst [c] (MOVQconst [d])) => (MOVQconst [int64(c)^d]) (XORLconst [c] (MOVLconst [d])) => (MOVLconst [c^d]) (NOTQ (MOVQconst [c])) => (MOVQconst [^c]) (NOTL (MOVLconst [c])) => (MOVLconst [^c]) (BTSQconst [c] (MOVQconst [d])) => (MOVQconst [d|(1< (MOVLconst [d|(1< (MOVQconst [d&^(1< (MOVLconst [d&^(1< (MOVQconst [d^(1< (MOVLconst [d^(1< (MOVQconst [c|d]) // generic simplifications // TODO: more of this (ADDQ x (NEGQ y)) => (SUBQ x y) (ADDL x (NEGL y)) => (SUBL x y) (SUBQ x x) => (MOVQconst [0]) (SUBL x x) => (MOVLconst [0]) (ANDQ x x) => x (ANDL x x) => x (ORQ x x) => x (ORL x x) => x (XORQ x x) => (MOVQconst [0]) (XORL x x) => (MOVLconst [0]) (SHLLconst [d] (MOVLconst [c])) => (MOVLconst [c << uint64(d)]) (SHLQconst [d] (MOVQconst [c])) => (MOVQconst [c << uint64(d)]) (SHLQconst [d] (MOVLconst [c])) => (MOVQconst [int64(c) << uint64(d)]) // Fold NEG into ADDconst/MULconst. Take care to keep c in 32 bit range. (NEGQ (ADDQconst [c] (NEGQ x))) && c != -(1<<31) => (ADDQconst [-c] x) (MULQconst [c] (NEGQ x)) && c != -(1<<31) => (MULQconst [-c] x) // checking AND against 0. (CMPQconst a:(ANDQ x y) [0]) && a.Uses == 1 => (TESTQ x y) (CMPLconst a:(ANDL x y) [0]) && a.Uses == 1 => (TESTL x y) (CMPWconst a:(ANDL x y) [0]) && a.Uses == 1 => (TESTW x y) (CMPBconst a:(ANDL x y) [0]) && a.Uses == 1 => (TESTB x y) (CMPQconst a:(ANDQconst [c] x) [0]) && a.Uses == 1 => (TESTQconst [c] x) (CMPLconst a:(ANDLconst [c] x) [0]) && a.Uses == 1 => (TESTLconst [c] x) (CMPWconst a:(ANDLconst [c] x) [0]) && a.Uses == 1 => (TESTWconst [int16(c)] x) (CMPBconst a:(ANDLconst [c] x) [0]) && a.Uses == 1 => (TESTBconst [int8(c)] x) // Convert TESTx to TESTxconst if possible. (TESTQ (MOVQconst [c]) x) && is32Bit(c) => (TESTQconst [int32(c)] x) (TESTL (MOVLconst [c]) x) => (TESTLconst [c] x) (TESTW (MOVLconst [c]) x) => (TESTWconst [int16(c)] x) (TESTB (MOVLconst [c]) x) => (TESTBconst [int8(c)] x) // TEST %reg,%reg is shorter than CMP (CMPQconst x [0]) => (TESTQ x x) (CMPLconst x [0]) => (TESTL x x) (CMPWconst x [0]) => (TESTW x x) (CMPBconst x [0]) => (TESTB x x) (TESTQconst [-1] x) && x.Op != OpAMD64MOVQconst => (TESTQ x x) (TESTLconst [-1] x) && x.Op != OpAMD64MOVLconst => (TESTL x x) (TESTWconst [-1] x) && x.Op != OpAMD64MOVLconst => (TESTW x x) (TESTBconst [-1] x) && x.Op != OpAMD64MOVLconst => (TESTB x x) // Convert LEAQ1 back to ADDQ if we can (LEAQ1 [0] x y) && v.Aux == nil => (ADDQ x y) // Combining byte loads into larger (unaligned) loads. // There are many ways these combinations could occur. This is // designed to match the way encoding/binary.LittleEndian does it. // Little-endian loads (OR(L|Q) x0:(MOVBload [i0] {s} p mem) sh:(SHL(L|Q)const [8] x1:(MOVBload [i1] {s} p mem))) && i1 == i0+1 && x0.Uses == 1 && x1.Uses == 1 && sh.Uses == 1 && mergePoint(b,x0,x1) != nil && clobber(x0, x1, sh) => @mergePoint(b,x0,x1) (MOVWload [i0] {s} p mem) (OR(L|Q) x0:(MOVBload [i] {s} p0 mem) sh:(SHL(L|Q)const [8] x1:(MOVBload [i] {s} p1 mem))) && x0.Uses == 1 && x1.Uses == 1 && sh.Uses == 1 && sequentialAddresses(p0, p1, 1) && mergePoint(b,x0,x1) != nil && clobber(x0, x1, sh) => @mergePoint(b,x0,x1) (MOVWload [i] {s} p0 mem) (OR(L|Q) x0:(MOVWload [i0] {s} p mem) sh:(SHL(L|Q)const [16] x1:(MOVWload [i1] {s} p mem))) && i1 == i0+2 && x0.Uses == 1 && x1.Uses == 1 && sh.Uses == 1 && mergePoint(b,x0,x1) != nil && clobber(x0, x1, sh) => @mergePoint(b,x0,x1) (MOVLload [i0] {s} p mem) (OR(L|Q) x0:(MOVWload [i] {s} p0 mem) sh:(SHL(L|Q)const [16] x1:(MOVWload [i] {s} p1 mem))) && x0.Uses == 1 && x1.Uses == 1 && sh.Uses == 1 && sequentialAddresses(p0, p1, 2) && mergePoint(b,x0,x1) != nil && clobber(x0, x1, sh) => @mergePoint(b,x0,x1) (MOVLload [i] {s} p0 mem) (ORQ x0:(MOVLload [i0] {s} p mem) sh:(SHLQconst [32] x1:(MOVLload [i1] {s} p mem))) && i1 == i0+4 && x0.Uses == 1 && x1.Uses == 1 && sh.Uses == 1 && mergePoint(b,x0,x1) != nil && clobber(x0, x1, sh) => @mergePoint(b,x0,x1) (MOVQload [i0] {s} p mem) (ORQ x0:(MOVLload [i] {s} p0 mem) sh:(SHLQconst [32] x1:(MOVLload [i] {s} p1 mem))) && x0.Uses == 1 && x1.Uses == 1 && sh.Uses == 1 && sequentialAddresses(p0, p1, 4) && mergePoint(b,x0,x1) != nil && clobber(x0, x1, sh) => @mergePoint(b,x0,x1) (MOVQload [i] {s} p0 mem) (OR(L|Q) s1:(SHL(L|Q)const [j1] x1:(MOVBload [i1] {s} p mem)) or:(OR(L|Q) s0:(SHL(L|Q)const [j0] x0:(MOVBload [i0] {s} p mem)) y)) && i1 == i0+1 && j1 == j0+8 && j0 % 16 == 0 && x0.Uses == 1 && x1.Uses == 1 && s0.Uses == 1 && s1.Uses == 1 && or.Uses == 1 && mergePoint(b,x0,x1,y) != nil && clobber(x0, x1, s0, s1, or) => @mergePoint(b,x0,x1,y) (OR(L|Q) (SHL(L|Q)const [j0] (MOVWload [i0] {s} p mem)) y) (OR(L|Q) s1:(SHL(L|Q)const [j1] x1:(MOVBload [i] {s} p1 mem)) or:(OR(L|Q) s0:(SHL(L|Q)const [j0] x0:(MOVBload [i] {s} p0 mem)) y)) && j1 == j0+8 && j0 % 16 == 0 && x0.Uses == 1 && x1.Uses == 1 && s0.Uses == 1 && s1.Uses == 1 && or.Uses == 1 && sequentialAddresses(p0, p1, 1) && mergePoint(b,x0,x1,y) != nil && clobber(x0, x1, s0, s1, or) => @mergePoint(b,x0,x1,y) (OR(L|Q) (SHL(L|Q)const [j0] (MOVWload [i] {s} p0 mem)) y) (ORQ s1:(SHLQconst [j1] x1:(MOVWload [i1] {s} p mem)) or:(ORQ s0:(SHLQconst [j0] x0:(MOVWload [i0] {s} p mem)) y)) && i1 == i0+2 && j1 == j0+16 && j0 % 32 == 0 && x0.Uses == 1 && x1.Uses == 1 && s0.Uses == 1 && s1.Uses == 1 && or.Uses == 1 && mergePoint(b,x0,x1,y) != nil && clobber(x0, x1, s0, s1, or) => @mergePoint(b,x0,x1,y) (ORQ (SHLQconst [j0] (MOVLload [i0] {s} p mem)) y) (ORQ s1:(SHLQconst [j1] x1:(MOVWload [i] {s} p1 mem)) or:(ORQ s0:(SHLQconst [j0] x0:(MOVWload [i] {s} p0 mem)) y)) && j1 == j0+16 && j0 % 32 == 0 && x0.Uses == 1 && x1.Uses == 1 && s0.Uses == 1 && s1.Uses == 1 && or.Uses == 1 && sequentialAddresses(p0, p1, 2) && mergePoint(b,x0,x1,y) != nil && clobber(x0, x1, s0, s1, or) => @mergePoint(b,x0,x1,y) (ORQ (SHLQconst [j0] (MOVLload [i] {s} p0 mem)) y) // Big-endian loads (OR(L|Q) x1:(MOVBload [i1] {s} p mem) sh:(SHL(L|Q)const [8] x0:(MOVBload [i0] {s} p mem))) && i1 == i0+1 && x0.Uses == 1 && x1.Uses == 1 && sh.Uses == 1 && mergePoint(b,x0,x1) != nil && clobber(x0, x1, sh) => @mergePoint(b,x0,x1) (ROLWconst [8] (MOVWload [i0] {s} p mem)) (OR(L|Q) x1:(MOVBload [i] {s} p1 mem) sh:(SHL(L|Q)const [8] x0:(MOVBload [i] {s} p0 mem))) && x0.Uses == 1 && x1.Uses == 1 && sh.Uses == 1 && sequentialAddresses(p0, p1, 1) && mergePoint(b,x0,x1) != nil && clobber(x0, x1, sh) => @mergePoint(b,x0,x1) (ROLWconst [8] (MOVWload [i] {s} p0 mem)) (OR(L|Q) r1:(ROLWconst [8] x1:(MOVWload [i1] {s} p mem)) sh:(SHL(L|Q)const [16] r0:(ROLWconst [8] x0:(MOVWload [i0] {s} p mem)))) && i1 == i0+2 && x0.Uses == 1 && x1.Uses == 1 && r0.Uses == 1 && r1.Uses == 1 && sh.Uses == 1 && mergePoint(b,x0,x1) != nil && clobber(x0, x1, r0, r1, sh) => @mergePoint(b,x0,x1) (BSWAPL (MOVLload [i0] {s} p mem)) (OR(L|Q) r1:(ROLWconst [8] x1:(MOVWload [i] {s} p1 mem)) sh:(SHL(L|Q)const [16] r0:(ROLWconst [8] x0:(MOVWload [i] {s} p0 mem)))) && x0.Uses == 1 && x1.Uses == 1 && r0.Uses == 1 && r1.Uses == 1 && sh.Uses == 1 && sequentialAddresses(p0, p1, 2) && mergePoint(b,x0,x1) != nil && clobber(x0, x1, r0, r1, sh) => @mergePoint(b,x0,x1) (BSWAPL (MOVLload [i] {s} p0 mem)) (ORQ r1:(BSWAPL x1:(MOVLload [i1] {s} p mem)) sh:(SHLQconst [32] r0:(BSWAPL x0:(MOVLload [i0] {s} p mem)))) && i1 == i0+4 && x0.Uses == 1 && x1.Uses == 1 && r0.Uses == 1 && r1.Uses == 1 && sh.Uses == 1 && mergePoint(b,x0,x1) != nil && clobber(x0, x1, r0, r1, sh) => @mergePoint(b,x0,x1) (BSWAPQ (MOVQload [i0] {s} p mem)) (ORQ r1:(BSWAPL x1:(MOVLload [i] {s} p1 mem)) sh:(SHLQconst [32] r0:(BSWAPL x0:(MOVLload [i] {s} p0 mem)))) && x0.Uses == 1 && x1.Uses == 1 && r0.Uses == 1 && r1.Uses == 1 && sh.Uses == 1 && sequentialAddresses(p0, p1, 4) && mergePoint(b,x0,x1) != nil && clobber(x0, x1, r0, r1, sh) => @mergePoint(b,x0,x1) (BSWAPQ (MOVQload [i] {s} p0 mem)) (OR(L|Q) s0:(SHL(L|Q)const [j0] x0:(MOVBload [i0] {s} p mem)) or:(OR(L|Q) s1:(SHL(L|Q)const [j1] x1:(MOVBload [i1] {s} p mem)) y)) && i1 == i0+1 && j1 == j0-8 && j1 % 16 == 0 && x0.Uses == 1 && x1.Uses == 1 && s0.Uses == 1 && s1.Uses == 1 && or.Uses == 1 && mergePoint(b,x0,x1,y) != nil && clobber(x0, x1, s0, s1, or) => @mergePoint(b,x0,x1,y) (OR(L|Q) (SHL(L|Q)const [j1] (ROLWconst [8] (MOVWload [i0] {s} p mem))) y) (OR(L|Q) s0:(SHL(L|Q)const [j0] x0:(MOVBload [i] {s} p0 mem)) or:(OR(L|Q) s1:(SHL(L|Q)const [j1] x1:(MOVBload [i] {s} p1 mem)) y)) && j1 == j0-8 && j1 % 16 == 0 && x0.Uses == 1 && x1.Uses == 1 && s0.Uses == 1 && s1.Uses == 1 && or.Uses == 1 && sequentialAddresses(p0, p1, 1) && mergePoint(b,x0,x1,y) != nil && clobber(x0, x1, s0, s1, or) => @mergePoint(b,x0,x1,y) (OR(L|Q) (SHL(L|Q)const [j1] (ROLWconst [8] (MOVWload [i] {s} p0 mem))) y) (ORQ s0:(SHLQconst [j0] r0:(ROLWconst [8] x0:(MOVWload [i0] {s} p mem))) or:(ORQ s1:(SHLQconst [j1] r1:(ROLWconst [8] x1:(MOVWload [i1] {s} p mem))) y)) && i1 == i0+2 && j1 == j0-16 && j1 % 32 == 0 && x0.Uses == 1 && x1.Uses == 1 && r0.Uses == 1 && r1.Uses == 1 && s0.Uses == 1 && s1.Uses == 1 && or.Uses == 1 && mergePoint(b,x0,x1,y) != nil && clobber(x0, x1, r0, r1, s0, s1, or) => @mergePoint(b,x0,x1,y) (ORQ (SHLQconst [j1] (BSWAPL (MOVLload [i0] {s} p mem))) y) (ORQ s0:(SHLQconst [j0] r0:(ROLWconst [8] x0:(MOVWload [i] {s} p0 mem))) or:(ORQ s1:(SHLQconst [j1] r1:(ROLWconst [8] x1:(MOVWload [i] {s} p1 mem))) y)) && j1 == j0-16 && j1 % 32 == 0 && x0.Uses == 1 && x1.Uses == 1 && r0.Uses == 1 && r1.Uses == 1 && s0.Uses == 1 && s1.Uses == 1 && or.Uses == 1 && sequentialAddresses(p0, p1, 2) && mergePoint(b,x0,x1,y) != nil && clobber(x0, x1, r0, r1, s0, s1, or) => @mergePoint(b,x0,x1,y) (ORQ (SHLQconst [j1] (BSWAPL (MOVLload [i] {s} p0 mem))) y) // Combine 2 byte stores + shift into rolw 8 + word store (MOVBstore [i] {s} p w x0:(MOVBstore [i-1] {s} p (SHRWconst [8] w) mem)) && x0.Uses == 1 && clobber(x0) => (MOVWstore [i-1] {s} p (ROLWconst [8] w) mem) (MOVBstore [i] {s} p1 w x0:(MOVBstore [i] {s} p0 (SHRWconst [8] w) mem)) && x0.Uses == 1 && sequentialAddresses(p0, p1, 1) && clobber(x0) => (MOVWstore [i] {s} p0 (ROLWconst [8] w) mem) // Combine stores + shifts into bswap and larger (unaligned) stores (MOVBstore [i] {s} p w x2:(MOVBstore [i-1] {s} p (SHRLconst [8] w) x1:(MOVBstore [i-2] {s} p (SHRLconst [16] w) x0:(MOVBstore [i-3] {s} p (SHRLconst [24] w) mem)))) && x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && clobber(x0, x1, x2) => (MOVLstore [i-3] {s} p (BSWAPL w) mem) (MOVBstore [i] {s} p3 w x2:(MOVBstore [i] {s} p2 (SHRLconst [8] w) x1:(MOVBstore [i] {s} p1 (SHRLconst [16] w) x0:(MOVBstore [i] {s} p0 (SHRLconst [24] w) mem)))) && x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && sequentialAddresses(p0, p1, 1) && sequentialAddresses(p1, p2, 1) && sequentialAddresses(p2, p3, 1) && clobber(x0, x1, x2) => (MOVLstore [i] {s} p0 (BSWAPL w) mem) (MOVBstore [i] {s} p w x6:(MOVBstore [i-1] {s} p (SHRQconst [8] w) x5:(MOVBstore [i-2] {s} p (SHRQconst [16] w) x4:(MOVBstore [i-3] {s} p (SHRQconst [24] w) x3:(MOVBstore [i-4] {s} p (SHRQconst [32] w) x2:(MOVBstore [i-5] {s} p (SHRQconst [40] w) x1:(MOVBstore [i-6] {s} p (SHRQconst [48] w) x0:(MOVBstore [i-7] {s} p (SHRQconst [56] w) mem)))))))) && x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && x4.Uses == 1 && x5.Uses == 1 && x6.Uses == 1 && clobber(x0, x1, x2, x3, x4, x5, x6) => (MOVQstore [i-7] {s} p (BSWAPQ w) mem) (MOVBstore [i] {s} p7 w x6:(MOVBstore [i] {s} p6 (SHRQconst [8] w) x5:(MOVBstore [i] {s} p5 (SHRQconst [16] w) x4:(MOVBstore [i] {s} p4 (SHRQconst [24] w) x3:(MOVBstore [i] {s} p3 (SHRQconst [32] w) x2:(MOVBstore [i] {s} p2 (SHRQconst [40] w) x1:(MOVBstore [i] {s} p1 (SHRQconst [48] w) x0:(MOVBstore [i] {s} p0 (SHRQconst [56] w) mem)))))))) && x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && x4.Uses == 1 && x5.Uses == 1 && x6.Uses == 1 && sequentialAddresses(p0, p1, 1) && sequentialAddresses(p1, p2, 1) && sequentialAddresses(p2, p3, 1) && sequentialAddresses(p3, p4, 1) && sequentialAddresses(p4, p5, 1) && sequentialAddresses(p5, p6, 1) && sequentialAddresses(p6, p7, 1) && clobber(x0, x1, x2, x3, x4, x5, x6) => (MOVQstore [i] {s} p0 (BSWAPQ w) mem) // Combine constant stores into larger (unaligned) stores. (MOVBstoreconst [c] {s} p x:(MOVBstoreconst [a] {s} p mem)) && x.Uses == 1 && a.Off() + 1 == c.Off() && clobber(x) => (MOVWstoreconst [makeValAndOff(a.Val()&0xff | c.Val()<<8, a.Off())] {s} p mem) (MOVBstoreconst [a] {s} p x:(MOVBstoreconst [c] {s} p mem)) && x.Uses == 1 && a.Off() + 1 == c.Off() && clobber(x) => (MOVWstoreconst [makeValAndOff(a.Val()&0xff | c.Val()<<8, a.Off())] {s} p mem) (MOVWstoreconst [c] {s} p x:(MOVWstoreconst [a] {s} p mem)) && x.Uses == 1 && a.Off() + 2 == c.Off() && clobber(x) => (MOVLstoreconst [makeValAndOff(a.Val()&0xffff | c.Val()<<16, a.Off())] {s} p mem) (MOVWstoreconst [a] {s} p x:(MOVWstoreconst [c] {s} p mem)) && x.Uses == 1 && a.Off() + 2 == c.Off() && clobber(x) => (MOVLstoreconst [makeValAndOff(a.Val()&0xffff | c.Val()<<16, a.Off())] {s} p mem) (MOVLstoreconst [c] {s} p x:(MOVLstoreconst [a] {s} p mem)) && x.Uses == 1 && a.Off() + 4 == c.Off() && clobber(x) => (MOVQstore [a.Off()] {s} p (MOVQconst [a.Val64()&0xffffffff | c.Val64()<<32]) mem) (MOVLstoreconst [a] {s} p x:(MOVLstoreconst [c] {s} p mem)) && x.Uses == 1 && a.Off() + 4 == c.Off() && clobber(x) => (MOVQstore [a.Off()] {s} p (MOVQconst [a.Val64()&0xffffffff | c.Val64()<<32]) mem) (MOVQstoreconst [c] {s} p x:(MOVQstoreconst [a] {s} p mem)) && config.useSSE && x.Uses == 1 && a.Off() + 8 == c.Off() && a.Val() == 0 && c.Val() == 0 && clobber(x) => (MOVOstoreconst [makeValAndOff(0,a.Off())] {s} p mem) (MOVQstoreconst [a] {s} p x:(MOVQstoreconst [c] {s} p mem)) && config.useSSE && x.Uses == 1 && a.Off() + 8 == c.Off() && a.Val() == 0 && c.Val() == 0 && clobber(x) => (MOVOstoreconst [makeValAndOff(0,a.Off())] {s} p mem) // Combine stores into larger (unaligned) stores. Little endian. (MOVBstore [i] {s} p (SHR(W|L|Q)const [8] w) x:(MOVBstore [i-1] {s} p w mem)) && x.Uses == 1 && clobber(x) => (MOVWstore [i-1] {s} p w mem) (MOVBstore [i] {s} p w x:(MOVBstore [i+1] {s} p (SHR(W|L|Q)const [8] w) mem)) && x.Uses == 1 && clobber(x) => (MOVWstore [i] {s} p w mem) (MOVBstore [i] {s} p (SHR(L|Q)const [j] w) x:(MOVBstore [i-1] {s} p w0:(SHR(L|Q)const [j-8] w) mem)) && x.Uses == 1 && clobber(x) => (MOVWstore [i-1] {s} p w0 mem) (MOVBstore [i] {s} p1 (SHR(W|L|Q)const [8] w) x:(MOVBstore [i] {s} p0 w mem)) && x.Uses == 1 && sequentialAddresses(p0, p1, 1) && clobber(x) => (MOVWstore [i] {s} p0 w mem) (MOVBstore [i] {s} p0 w x:(MOVBstore [i] {s} p1 (SHR(W|L|Q)const [8] w) mem)) && x.Uses == 1 && sequentialAddresses(p0, p1, 1) && clobber(x) => (MOVWstore [i] {s} p0 w mem) (MOVBstore [i] {s} p1 (SHR(L|Q)const [j] w) x:(MOVBstore [i] {s} p0 w0:(SHR(L|Q)const [j-8] w) mem)) && x.Uses == 1 && sequentialAddresses(p0, p1, 1) && clobber(x) => (MOVWstore [i] {s} p0 w0 mem) (MOVWstore [i] {s} p (SHR(L|Q)const [16] w) x:(MOVWstore [i-2] {s} p w mem)) && x.Uses == 1 && clobber(x) => (MOVLstore [i-2] {s} p w mem) (MOVWstore [i] {s} p (SHR(L|Q)const [j] w) x:(MOVWstore [i-2] {s} p w0:(SHR(L|Q)const [j-16] w) mem)) && x.Uses == 1 && clobber(x) => (MOVLstore [i-2] {s} p w0 mem) (MOVWstore [i] {s} p1 (SHR(L|Q)const [16] w) x:(MOVWstore [i] {s} p0 w mem)) && x.Uses == 1 && sequentialAddresses(p0, p1, 2) && clobber(x) => (MOVLstore [i] {s} p0 w mem) (MOVWstore [i] {s} p1 (SHR(L|Q)const [j] w) x:(MOVWstore [i] {s} p0 w0:(SHR(L|Q)const [j-16] w) mem)) && x.Uses == 1 && sequentialAddresses(p0, p1, 2) && clobber(x) => (MOVLstore [i] {s} p0 w0 mem) (MOVLstore [i] {s} p (SHRQconst [32] w) x:(MOVLstore [i-4] {s} p w mem)) && x.Uses == 1 && clobber(x) => (MOVQstore [i-4] {s} p w mem) (MOVLstore [i] {s} p (SHRQconst [j] w) x:(MOVLstore [i-4] {s} p w0:(SHRQconst [j-32] w) mem)) && x.Uses == 1 && clobber(x) => (MOVQstore [i-4] {s} p w0 mem) (MOVLstore [i] {s} p1 (SHRQconst [32] w) x:(MOVLstore [i] {s} p0 w mem)) && x.Uses == 1 && sequentialAddresses(p0, p1, 4) && clobber(x) => (MOVQstore [i] {s} p0 w mem) (MOVLstore [i] {s} p1 (SHRQconst [j] w) x:(MOVLstore [i] {s} p0 w0:(SHRQconst [j-32] w) mem)) && x.Uses == 1 && sequentialAddresses(p0, p1, 4) && clobber(x) => (MOVQstore [i] {s} p0 w0 mem) (MOVBstore [7] {s} p1 (SHRQconst [56] w) x1:(MOVWstore [5] {s} p1 (SHRQconst [40] w) x2:(MOVLstore [1] {s} p1 (SHRQconst [8] w) x3:(MOVBstore [0] {s} p1 w mem)))) && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && clobber(x1, x2, x3) => (MOVQstore {s} p1 w mem) (MOVBstore [i] {s} p x1:(MOVBload [j] {s2} p2 mem) mem2:(MOVBstore [i-1] {s} p x2:(MOVBload [j-1] {s2} p2 mem) mem)) && x1.Uses == 1 && x2.Uses == 1 && mem2.Uses == 1 && clobber(x1, x2, mem2) => (MOVWstore [i-1] {s} p (MOVWload [j-1] {s2} p2 mem) mem) (MOVWstore [i] {s} p x1:(MOVWload [j] {s2} p2 mem) mem2:(MOVWstore [i-2] {s} p x2:(MOVWload [j-2] {s2} p2 mem) mem)) && x1.Uses == 1 && x2.Uses == 1 && mem2.Uses == 1 && clobber(x1, x2, mem2) => (MOVLstore [i-2] {s} p (MOVLload [j-2] {s2} p2 mem) mem) (MOVLstore [i] {s} p x1:(MOVLload [j] {s2} p2 mem) mem2:(MOVLstore [i-4] {s} p x2:(MOVLload [j-4] {s2} p2 mem) mem)) && x1.Uses == 1 && x2.Uses == 1 && mem2.Uses == 1 && clobber(x1, x2, mem2) => (MOVQstore [i-4] {s} p (MOVQload [j-4] {s2} p2 mem) mem) // Merge load and op // TODO: add indexed variants? ((ADD|SUB|AND|OR|XOR)Q x l:(MOVQload [off] {sym} ptr mem)) && canMergeLoadClobber(v, l, x) && clobber(l) => ((ADD|SUB|AND|OR|XOR)Qload x [off] {sym} ptr mem) ((ADD|SUB|AND|OR|XOR)L x l:(MOVLload [off] {sym} ptr mem)) && canMergeLoadClobber(v, l, x) && clobber(l) => ((ADD|SUB|AND|OR|XOR)Lload x [off] {sym} ptr mem) ((ADD|SUB|MUL|DIV)SD x l:(MOVSDload [off] {sym} ptr mem)) && canMergeLoadClobber(v, l, x) && clobber(l) => ((ADD|SUB|MUL|DIV)SDload x [off] {sym} ptr mem) ((ADD|SUB|MUL|DIV)SS x l:(MOVSSload [off] {sym} ptr mem)) && canMergeLoadClobber(v, l, x) && clobber(l) => ((ADD|SUB|MUL|DIV)SSload x [off] {sym} ptr mem) (MOVLstore {sym} [off] ptr y:((ADD|AND|OR|XOR)Lload x [off] {sym} ptr mem) mem) && y.Uses==1 && clobber(y) => ((ADD|AND|OR|XOR)Lmodify [off] {sym} ptr x mem) (MOVLstore {sym} [off] ptr y:((ADD|SUB|AND|OR|XOR)L l:(MOVLload [off] {sym} ptr mem) x) mem) && y.Uses==1 && l.Uses==1 && clobber(y, l) => ((ADD|SUB|AND|OR|XOR)Lmodify [off] {sym} ptr x mem) (MOVQstore {sym} [off] ptr y:((ADD|AND|OR|XOR)Qload x [off] {sym} ptr mem) mem) && y.Uses==1 && clobber(y) => ((ADD|AND|OR|XOR)Qmodify [off] {sym} ptr x mem) (MOVQstore {sym} [off] ptr y:((ADD|SUB|AND|OR|XOR)Q l:(MOVQload [off] {sym} ptr mem) x) mem) && y.Uses==1 && l.Uses==1 && clobber(y, l) => ((ADD|SUB|AND|OR|XOR)Qmodify [off] {sym} ptr x mem) // Merge ADDQconst and LEAQ into atomic loads. (MOV(Q|L|B)atomicload [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(int64(off1)+int64(off2)) => (MOV(Q|L|B)atomicload [off1+off2] {sym} ptr mem) (MOV(Q|L|B)atomicload [off1] {sym1} (LEAQ [off2] {sym2} ptr) mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) => (MOV(Q|L|B)atomicload [off1+off2] {mergeSym(sym1, sym2)} ptr mem) // Merge ADDQconst and LEAQ into atomic stores. (XCHGQ [off1] {sym} val (ADDQconst [off2] ptr) mem) && is32Bit(int64(off1)+int64(off2)) => (XCHGQ [off1+off2] {sym} val ptr mem) (XCHGQ [off1] {sym1} val (LEAQ [off2] {sym2} ptr) mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) && ptr.Op != OpSB => (XCHGQ [off1+off2] {mergeSym(sym1,sym2)} val ptr mem) (XCHGL [off1] {sym} val (ADDQconst [off2] ptr) mem) && is32Bit(int64(off1)+int64(off2)) => (XCHGL [off1+off2] {sym} val ptr mem) (XCHGL [off1] {sym1} val (LEAQ [off2] {sym2} ptr) mem) && is32Bit(int64(off1)+int64(off2)) && canMergeSym(sym1, sym2) && ptr.Op != OpSB => (XCHGL [off1+off2] {mergeSym(sym1,sym2)} val ptr mem) // Merge ADDQconst into atomic adds. // TODO: merging LEAQ doesn't work, assembler doesn't like the resulting instructions. (XADDQlock [off1] {sym} val (ADDQconst [off2] ptr) mem) && is32Bit(int64(off1)+int64(off2)) => (XADDQlock [off1+off2] {sym} val ptr mem) (XADDLlock [off1] {sym} val (ADDQconst [off2] ptr) mem) && is32Bit(int64(off1)+int64(off2)) => (XADDLlock [off1+off2] {sym} val ptr mem) // Merge ADDQconst into atomic compare and swaps. // TODO: merging LEAQ doesn't work, assembler doesn't like the resulting instructions. (CMPXCHGQlock [off1] {sym} (ADDQconst [off2] ptr) old new_ mem) && is32Bit(int64(off1)+int64(off2)) => (CMPXCHGQlock [off1+off2] {sym} ptr old new_ mem) (CMPXCHGLlock [off1] {sym} (ADDQconst [off2] ptr) old new_ mem) && is32Bit(int64(off1)+int64(off2)) => (CMPXCHGLlock [off1+off2] {sym} ptr old new_ mem) // We don't need the conditional move if we know the arg of BSF is not zero. (CMOVQEQ x _ (Select1 (BSFQ (ORQconst [c] _)))) && c != 0 => x // Extension is unnecessary for trailing zeros. (BSFQ (ORQconst [1<<8] (MOVBQZX x))) => (BSFQ (ORQconst [1<<8] x)) (BSFQ (ORQconst [1<<16] (MOVWQZX x))) => (BSFQ (ORQconst [1<<16] x)) // Redundant sign/zero extensions // Note: see issue 21963. We have to make sure we use the right type on // the resulting extension (the outer type, not the inner type). (MOVLQSX (MOVLQSX x)) => (MOVLQSX x) (MOVLQSX (MOVWQSX x)) => (MOVWQSX x) (MOVLQSX (MOVBQSX x)) => (MOVBQSX x) (MOVWQSX (MOVWQSX x)) => (MOVWQSX x) (MOVWQSX (MOVBQSX x)) => (MOVBQSX x) (MOVBQSX (MOVBQSX x)) => (MOVBQSX x) (MOVLQZX (MOVLQZX x)) => (MOVLQZX x) (MOVLQZX (MOVWQZX x)) => (MOVWQZX x) (MOVLQZX (MOVBQZX x)) => (MOVBQZX x) (MOVWQZX (MOVWQZX x)) => (MOVWQZX x) (MOVWQZX (MOVBQZX x)) => (MOVBQZX x) (MOVBQZX (MOVBQZX x)) => (MOVBQZX x) (MOVQstore [off] {sym} ptr a:((ADD|AND|OR|XOR)Qconst [c] l:(MOVQload [off] {sym} ptr2 mem)) mem) && isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && clobber(l, a) => ((ADD|AND|OR|XOR)Qconstmodify {sym} [makeValAndOff(int32(c),off)] ptr mem) (MOVLstore [off] {sym} ptr a:((ADD|AND|OR|XOR)Lconst [c] l:(MOVLload [off] {sym} ptr2 mem)) mem) && isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && clobber(l, a) => ((ADD|AND|OR|XOR)Lconstmodify {sym} [makeValAndOff(int32(c),off)] ptr mem) // float <-> int register moves, with no conversion. // These come up when compiling math.{Float{32,64}bits,Float{32,64}frombits}. (MOVQload [off] {sym} ptr (MOVSDstore [off] {sym} ptr val _)) => (MOVQf2i val) (MOVLload [off] {sym} ptr (MOVSSstore [off] {sym} ptr val _)) => (MOVLf2i val) (MOVSDload [off] {sym} ptr (MOVQstore [off] {sym} ptr val _)) => (MOVQi2f val) (MOVSSload [off] {sym} ptr (MOVLstore [off] {sym} ptr val _)) => (MOVLi2f val) // Other load-like ops. (ADDQload x [off] {sym} ptr (MOVSDstore [off] {sym} ptr y _)) => (ADDQ x (MOVQf2i y)) (ADDLload x [off] {sym} ptr (MOVSSstore [off] {sym} ptr y _)) => (ADDL x (MOVLf2i y)) (SUBQload x [off] {sym} ptr (MOVSDstore [off] {sym} ptr y _)) => (SUBQ x (MOVQf2i y)) (SUBLload x [off] {sym} ptr (MOVSSstore [off] {sym} ptr y _)) => (SUBL x (MOVLf2i y)) (ANDQload x [off] {sym} ptr (MOVSDstore [off] {sym} ptr y _)) => (ANDQ x (MOVQf2i y)) (ANDLload x [off] {sym} ptr (MOVSSstore [off] {sym} ptr y _)) => (ANDL x (MOVLf2i y)) ( ORQload x [off] {sym} ptr (MOVSDstore [off] {sym} ptr y _)) => ( ORQ x (MOVQf2i y)) ( ORLload x [off] {sym} ptr (MOVSSstore [off] {sym} ptr y _)) => ( ORL x (MOVLf2i y)) (XORQload x [off] {sym} ptr (MOVSDstore [off] {sym} ptr y _)) => (XORQ x (MOVQf2i y)) (XORLload x [off] {sym} ptr (MOVSSstore [off] {sym} ptr y _)) => (XORL x (MOVLf2i y)) (ADDSDload x [off] {sym} ptr (MOVQstore [off] {sym} ptr y _)) => (ADDSD x (MOVQi2f y)) (ADDSSload x [off] {sym} ptr (MOVLstore [off] {sym} ptr y _)) => (ADDSS x (MOVLi2f y)) (SUBSDload x [off] {sym} ptr (MOVQstore [off] {sym} ptr y _)) => (SUBSD x (MOVQi2f y)) (SUBSSload x [off] {sym} ptr (MOVLstore [off] {sym} ptr y _)) => (SUBSS x (MOVLi2f y)) (MULSDload x [off] {sym} ptr (MOVQstore [off] {sym} ptr y _)) => (MULSD x (MOVQi2f y)) (MULSSload x [off] {sym} ptr (MOVLstore [off] {sym} ptr y _)) => (MULSS x (MOVLi2f y)) // Redirect stores to use the other register set. (MOVQstore [off] {sym} ptr (MOVQf2i val) mem) => (MOVSDstore [off] {sym} ptr val mem) (MOVLstore [off] {sym} ptr (MOVLf2i val) mem) => (MOVSSstore [off] {sym} ptr val mem) (MOVSDstore [off] {sym} ptr (MOVQi2f val) mem) => (MOVQstore [off] {sym} ptr val mem) (MOVSSstore [off] {sym} ptr (MOVLi2f val) mem) => (MOVLstore [off] {sym} ptr val mem) // Load args directly into the register class where it will be used. // We do this by just modifying the type of the Arg. (MOVQf2i (Arg [off] {sym})) && t.Size() == u.Size() => @b.Func.Entry (Arg [off] {sym}) (MOVLf2i (Arg [off] {sym})) && t.Size() == u.Size() => @b.Func.Entry (Arg [off] {sym}) (MOVQi2f (Arg [off] {sym})) && t.Size() == u.Size() => @b.Func.Entry (Arg [off] {sym}) (MOVLi2f (Arg [off] {sym})) && t.Size() == u.Size() => @b.Func.Entry (Arg [off] {sym}) // LEAQ is rematerializeable, so this helps to avoid register spill. // See issue 22947 for details (ADD(Q|L)const [off] x:(SP)) => (LEA(Q|L) [off] x) // HMULx is commutative, but its first argument must go in AX. // If possible, put a rematerializeable value in the first argument slot, // to reduce the odds that another value will be have to spilled // specifically to free up AX. (HMUL(Q|L) x y) && !x.rematerializeable() && y.rematerializeable() => (HMUL(Q|L) y x) (HMUL(Q|L)U x y) && !x.rematerializeable() && y.rematerializeable() => (HMUL(Q|L)U y x) // Fold loads into compares // Note: these may be undone by the flagalloc pass. (CMP(Q|L|W|B) l:(MOV(Q|L|W|B)load {sym} [off] ptr mem) x) && canMergeLoad(v, l) && clobber(l) => (CMP(Q|L|W|B)load {sym} [off] ptr x mem) (CMP(Q|L|W|B) x l:(MOV(Q|L|W|B)load {sym} [off] ptr mem)) && canMergeLoad(v, l) && clobber(l) => (InvertFlags (CMP(Q|L|W|B)load {sym} [off] ptr x mem)) (CMP(Q|L)const l:(MOV(Q|L)load {sym} [off] ptr mem) [c]) && l.Uses == 1 && clobber(l) => @l.Block (CMP(Q|L)constload {sym} [makeValAndOff(c,off)] ptr mem) (CMP(W|B)const l:(MOV(W|B)load {sym} [off] ptr mem) [c]) && l.Uses == 1 && clobber(l) => @l.Block (CMP(W|B)constload {sym} [makeValAndOff(int32(c),off)] ptr mem) (CMPQload {sym} [off] ptr (MOVQconst [c]) mem) && validVal(c) => (CMPQconstload {sym} [makeValAndOff(int32(c),off)] ptr mem) (CMPLload {sym} [off] ptr (MOVLconst [c]) mem) => (CMPLconstload {sym} [makeValAndOff(c,off)] ptr mem) (CMPWload {sym} [off] ptr (MOVLconst [c]) mem) => (CMPWconstload {sym} [makeValAndOff(int32(int16(c)),off)] ptr mem) (CMPBload {sym} [off] ptr (MOVLconst [c]) mem) => (CMPBconstload {sym} [makeValAndOff(int32(int8(c)),off)] ptr mem) (TEST(Q|L|W|B) l:(MOV(Q|L|W|B)load {sym} [off] ptr mem) l2) && l == l2 && l.Uses == 2 && clobber(l) => @l.Block (CMP(Q|L|W|B)constload {sym} [makeValAndOff(0, off)] ptr mem) // Convert ANDload to MOVload when we can do the AND in a containing TEST op. // Only do when it's within the same block, so we don't have flags live across basic block boundaries. // See issue 44228. (TEST(Q|L) a:(AND(Q|L)load [off] {sym} x ptr mem) a) && a.Uses == 2 && a.Block == v.Block && clobber(a) => (TEST(Q|L) (MOV(Q|L)load [off] {sym} ptr mem) x) (MOVBload [off] {sym} (SB) _) && symIsRO(sym) => (MOVLconst [int32(read8(sym, int64(off)))]) (MOVWload [off] {sym} (SB) _) && symIsRO(sym) => (MOVLconst [int32(read16(sym, int64(off), config.ctxt.Arch.ByteOrder))]) (MOVLload [off] {sym} (SB) _) && symIsRO(sym) => (MOVQconst [int64(read32(sym, int64(off), config.ctxt.Arch.ByteOrder))]) (MOVQload [off] {sym} (SB) _) && symIsRO(sym) => (MOVQconst [int64(read64(sym, int64(off), config.ctxt.Arch.ByteOrder))]) (MOVOstore [dstOff] {dstSym} ptr (MOVOload [srcOff] {srcSym} (SB) _) mem) && symIsRO(srcSym) => (MOVQstore [dstOff+8] {dstSym} ptr (MOVQconst [int64(read64(srcSym, int64(srcOff)+8, config.ctxt.Arch.ByteOrder))]) (MOVQstore [dstOff] {dstSym} ptr (MOVQconst [int64(read64(srcSym, int64(srcOff), config.ctxt.Arch.ByteOrder))]) mem)) // Arch-specific inlining for small or disjoint runtime.memmove // Match post-lowering calls, memory version. (SelectN [0] call:(CALLstatic {sym} s1:(MOVQstoreconst _ [sc] s2:(MOVQstore _ src s3:(MOVQstore _ dst mem))))) && sc.Val64() >= 0 && isSameCall(sym, "runtime.memmove") && s1.Uses == 1 && s2.Uses == 1 && s3.Uses == 1 && isInlinableMemmove(dst, src, sc.Val64(), config) && clobber(s1, s2, s3, call) => (Move [sc.Val64()] dst src mem) // Match post-lowering calls, register version. (SelectN [0] call:(CALLstatic {sym} dst src (MOVQconst [sz]) mem)) && sz >= 0 && isSameCall(sym, "runtime.memmove") && call.Uses == 1 && isInlinableMemmove(dst, src, sz, config) && clobber(call) => (Move [sz] dst src mem) // Prefetch instructions (PrefetchCache ...) => (PrefetchT0 ...) (PrefetchCacheStreamed ...) => (PrefetchNTA ...) // CPUID feature: BMI1. (AND(Q|L) x (NOT(Q|L) y)) && buildcfg.GOAMD64 >= 3 => (ANDN(Q|L) x y) (AND(Q|L) x (NEG(Q|L) x)) && buildcfg.GOAMD64 >= 3 => (BLSI(Q|L) x) (XOR(Q|L) x (ADD(Q|L)const [-1] x)) && buildcfg.GOAMD64 >= 3 => (BLSMSK(Q|L) x) (AND(Q|L) x (ADD(Q|L)const [-1] x)) && buildcfg.GOAMD64 >= 3 => (BLSR(Q|L) x) (BSWAP(Q|L) (BSWAP(Q|L) p)) => p // CPUID feature: MOVBE. (MOV(Q|L)store [i] {s} p x:(BSWAP(Q|L) w) mem) && x.Uses == 1 && buildcfg.GOAMD64 >= 3 => (MOVBE(Q|L)store [i] {s} p w mem) (BSWAP(Q|L) x:(MOV(Q|L)load [i] {s} p mem)) && x.Uses == 1 && buildcfg.GOAMD64 >= 3 => (MOVBE(Q|L)load [i] {s} p mem) (BSWAP(Q|L) (MOVBE(Q|L)load [i] {s} p m)) => (MOV(Q|L)load [i] {s} p m) (MOVBE(Q|L)store [i] {s} p (BSWAP(Q|L) x) m) => (MOV(Q|L)store [i] {s} p x m) (ORQ x0:(MOVBELload [i0] {s} p mem) sh:(SHLQconst [32] x1:(MOVBELload [i1] {s} p mem))) && i0 == i1+4 && x0.Uses == 1 && x1.Uses == 1 && sh.Uses == 1 && mergePoint(b,x0,x1) != nil && clobber(x0, x1, sh) => @mergePoint(b,x0,x1) (MOVBEQload [i1] {s} p mem) (ORQ x0:(MOVBELload [i] {s} p0 mem) sh:(SHLQconst [32] x1:(MOVBELload [i] {s} p1 mem))) && x0.Uses == 1 && x1.Uses == 1 && sh.Uses == 1 && sequentialAddresses(p1, p0, 4) && mergePoint(b,x0,x1) != nil && clobber(x0, x1, sh) => @mergePoint(b,x0,x1) (MOVBEQload [i] {s} p1 mem)